METHODS FOR TREATING RHINITIS AND CONJUNCTIVITIS
Apparatus, methods, and kits for treating symptoms associated with common ailments, such as headaches, rhinitis, asthma, epilepsy, nervous disorders and the like, are provided. The apparatus comprises dispensers for carbon dioxide and other therapeutic gases. The methods comprise delivering small volumes of these gases to patients in a manner where the gas infuses into a body region in order to bathe the mucous membranes therein. It has been found that even very short exposure of patients to small volumes and high concentrations of such gases can provide significant relief from symptoms.
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This application is a continuation of U.S. application Ser. No. 11/200,649, (Attorney Docket No. 020017-000130US), filed Aug. 9, 2005, which was a continuation of U.S. application Ser. No. 09/614,389 (Attorney Docket No. 020017-000110US), (now U.S. Pat. No. 7,017,573), filed Jul. 12, 2002, which claims the benefit of U.S. Provisional Application Nos. 60/143,164, filed on Jul. 12, 1999; 60/148,736, filed on Aug. 16, 1999; 60/164,125, filed on Nov. 8, 1999, and 60/185,495 filed on Feb. 28, 2000, under 37 CFR §1.78. The full disclosures of each of these applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION1. Field of the Invention
The present invention relates generally to medical apparatus and methods. In particular, the present invention relates to methods and devices for delivering carbon dioxide and other gases to patients for relieving symptoms associated with headache (e.g., migraine headaches, tension-type headaches, cluster headaches), jaw pain, facial pain (e.g., trigeminal neuralgia), allergies (rhinitis and conjunctivitis), asthma, nervous disorders (e.g., epilepsy, Parkinson's), and other common ailments.
A walk through the headache and allergy section of any pharmacy quickly reveals that there is wide spread interest in remedies for relieving symptoms commonly associated with headaches, allergies, asthma, and other common ailments. The commonly available therapies include oral medicines, nasal sprays, oral inhalers, nasal inhalers, eye drops, and nose drops, and probably other devices and approaches that have been developed over the years. Still more possible therapies are available from the pharmacy with a prescription from a patient's doctor (e.g., injectables, inhalables). Despite the very large number of therapies which are available, no one therapy meets all patient needs, and many of the therapies suffer from very significant shortcomings. For example, present day therapies are slow-acting, have numerous adverse side effects (e.g., nausea, drowsiness, rebound headache from analgesic overuse, rebound congestion from decongestant overuse, dizziness, sedation, addiction, and numerous others), have low efficacy, and are contraindicated for a large portion of patients (e.g., those with hypertension, coronary artery disease, cerebrovascular disease, peptic ulcers, pregnancy, concurrent medications that would interact, children, elderly, and others). Suffice it to say that there is a continuing interest in providing improved methods and apparatus for treating such common symptoms and ailments.
The use of diluted carbon dioxide by inhalation for treating symptoms related to headaches, allergies, asthma, nervous disorders, and other common ailments was demonstrated in the 1940's and 1950's. The treatment protocols generally rely on breathing masks or other equipment for delivering relatively large volumes of dilute carbon dioxide for the patient to inhale through the mouth and/or the nose into the lungs until they become unconscious. The efficacy of this treatment depends upon the systemic effects of the inhaled gas and therefore require large volumes of gas. Typical carbon dioxide volumes inhaled were in the range from 0.5 to 25 liters of 30% to 70% carbon dioxide diluted in oxygen during a single treatment which was repeated several times a week for 25 to 50 treatments. While the use of inhaled carbon dioxide has proven to be quite effective for a number of indications, the wide spread use of carbon dioxide delivered in this manner never became popular. It is limited by the necessity of making the patient unconscious, the length of the treatment time and course, and the necessarily large, bulky non-portable gas cylinders and physician administration it requires. Most prior systems are so large and heavy they must be wheeled about using a dolly or a cart, and thus do not lend themselves to use outside of the hospital or home. While hand-held carbon dioxide dispensers have been proposed (for other purposes such as the treatment of hyperventilation), they are designed to deliver large volumes of dilute carbon dioxide for inhalation.
For these reasons, it would be desirable to provide improved apparatus and methods for treating the symptoms normally associated with headaches, allergies, asthma, and the like. Such apparatus and methods should provide small volumes of gas for convenient use away from the home, substantially immediate relief of symptoms, safety with few or no side effects, efficacy without requiring unconsciousness, efficacy in a large number of patients, therapy for those contraindicated for present day therapies, therapy without interaction with concurrent medications, low cost, a long life (in at least some embodiments), and permit the patient to administer the therapy and adapt the product usage for maximum comfort and effectiveness. At least some of these objectives will be met by the inventions described hereinafter.
2. Description of the Background Art
U.S. Pat. No. 3,776,227, describes a hand-held dispenser that delivers dilute carbon dioxide intended for the treatment of hyperventilation by inhalation. In addition, this hand-held dispenser is not designed to deliver carbon dioxide at high concentrations which are unbreathable. Other inhalation devices, systems, and methods for delivering carbon dioxide and other gases and aerosols to patients are described in U.S. Pat. Nos. 3,513,843; 3,870,072; 3,974,830; 4,137,914; 4,554,916; 5,262,180; 5,485,827; and 5,570,683.
Gas therapy for the treatment of headaches, allergies, asthma, and other conditions as well as associated physiology is described in the following references in the medical literature:
A. Carbon Dioxide Therapy
- Diamond, S. Migraine headache—its diagnosis and treatment. 13th Annual Practicing Physician's Approach to the Difficult Headache Patient, Rancho Mirage, Calif., Feb. 5-19, 2000
- Fisher H K et al., Am Rev Respir Dis 114(5):861, November 1976
- Fisher H K et al., Am Rev Respir Dis 101:855-896, 1970
- Gillman M A et al, Br J Psychiatry 159:672-5, 1991
- Grosshans V A et al., Z Gesamte Inn Med 42(23):667-70, 1987
- Harrowes W M C, Selinger Z Fractional administration of carbon dioxide in the treatment of neuroses, in Carbon Dioxide Therapy A Neurophysiological Treatment of Nervous Disorders. Second Edition. L J Meduna Ed, Charles C. Thomas publisher, Springfield, Ill. 1958
- Jozefowicz R F Neurologic Manifestations of Systemic Disease 7(3):605-616, August 1989
- LaVerne A A Dis Nerv System 14:5, 1953
- Leake C D et al, Calif West Med 31:20, 1929
- Loevenhart A S et al. JAMA 92 (11), 1929
- MacRae, D. Carbon dioxide in pediatrics, in Carbon Dioxide Therapy A Neurophysiological Treatment of Nervous Disorders. Second Edition. L J Meduna ed, Charles C. Thomas publisher, Springfield, Ill., 1958
- Marcussen R M, Wolff H G, Arch Neurol Psychiatry 63:42-51, 1950
- Meduna L J Dis Nerv System 8(2), 1947
- Meduna L J J Nerv & Ment Dis 108:373, 1948
- Meduna L J Ed, Carbon Dioxide Therapy A Neurophysiological Treatment of Nervous Disorders. Second Edition. Charles C. Thomas publisher, Springfield, Ill. 1958
- Moriarty J D Prognosis with carbon dioxide therapy, including the epinephrine-mecholyl test (Funkenstein test), in Carbon Dioxide Therapy A Neurophysiological Treatment of Nervous Disorders. Second Edition. L J Meduna Ed, Charles C. Thomas publisher, Springfield, Ill., 1958
- Moriarty J D J Clin & Exper Psychopath 13(3), 1952
- National Headache Foundation. A patients guide to migraine prevention & treatment, Chicago, Ill., August 1996.
- Rodarte J R et al., Resp Physiol 17:135-145, 1973
- Singh V et al., Lancet 335:1381-3, 1990
- Wilkinson W E Some clinical observations pertaining to the effects of carbon dioxide on the biology of mental disease, in Carbon Dioxide Therapy A Neurophysiological Treatment of Nervous Disorders. Second Edition. L J Meduna Ed, Charles C. Thomas publisher, Springfield, Ill., 1958
- Wilmoth D F et al., AACN Clin Issues 7(4):473-81, November 1996
B. Nitric Oxide Therapy
- Pagano D et al., Eur J Cardiothorac Surg 10(12):1120-6, 1996
- Ream R S et al., Crit Care Med 27(5):989-96, May 1999
- Schenk Pet al., Ann Emerg Med 33(6):710-4, June 1999
C. Helium Therapy
- Hollman G et al Crit Care Med 26(10):1731-6, October 1998
- Jolliet P et al Crit Care Med 27(11):2422-9, November 1999
- Schaeffer E M et al Crit Care Med 27(12):2666-70, December 1999
D Physiology
- Aizawa et al., Eur Respir J 13(4):775-80, April 1999
- Cha E J et al., J Appl Physiol 62(4):1544-50, April 1987
- Fiermonte G et al. Acta Neurol Scand 92(2):166-9, August 1995
- Glovsky M M Cur Opin in Pulm Med 4:54-58, 1998
- Leake C D Sci Monthly 20:320, 1925
- Loh E et al., Ann Thorac Surg 67(5):1380-5, May 1999
- Lorente de No' R Studies of the Rockefeller Institute 131:148-194, 1947
- Nielsen T M et al., Acta Physiol Scand 98(2):192-9, October 1976
- Saqueton C B et al., Am J Physiol 276(6 Pt 1):L925-L932, June 1999
- Schuttauf F et al Opthalmologe 95(4):225-8, April 1998
- Sterling G M et al., J of Appl Physiol 32(1):39-43, January 1972
- Tang A et al., Clinical Research 20:243, 1972
According to the present invention, methods, apparatus, and kits are provided for relieving symptoms associated with a variety of common ailments, particularly headaches, rhinitis, asthma, and epilepsy. Specific symptoms include head pain, jaw pain, facial pain, sinus congestion, sneezing, itchy throat, itchy eyes, rhinorrhea, difficulty breathing, seizures, and the like. This list of ailments and symptoms is not meant to be exhaustive, and the present invention may find use with other disorders where infusion with the treatment gases described hereinafter are found to provide for symptomatic relief. The inventions allow delivery of a small volume of therapeutic gas at high concentration directly into the nasal passages locally without inhalation providing faster relief without the adverse side effects of systemic drugs that are ingested, injected, or inhaled.
The present invention relies on infusing or bathing the mucous membranes of a body region of a patient, e.g., nasal and/or oral and/or ocular, with a treatment gas that induces a therapeutic effect relieving symptoms. An exemplary treatment gas is carbon dioxide but other gases such as nitric oxide, oxygen, isocapnic mixtures of gaseous acids, helium, and the like, will also find use The therapeutic gases (referred to herein as “therapeutic gases”) may be used in a substantially pure form without other gases, active agents, or other substances that dilute the therapeutic gas or that have other biological activities. In other instances, however, the therapeutic gases may be combined with other gases, such as inert carrier gases, active gases, solids to form aerosols, liquid droplets to form aerosols, sprays, powders, or the like to potentiate (enhance) their effects.
Conversely, these agents combined with the therapeutic gas can potentiate the effects of the therapeutic gas. In such instances, the therapeutic gases and mixtures may have biological activities in addition to the relief of symptoms accompanying common ailments, as described above. In all instances, however, the carbon dioxide or other principle therapeutic gas will be delivered in a quantity and over a time course that results in the reduction or elimination of the symptom that is being treated. A preferred aspect of the present invention is providing the patient with the ability to select a rate of infusive gas flow and total gas dose that are effective and tolerable for the particular patient, which flow rate and dose are generally much smaller than those employed in previous art.
The present invention provides for the desired symptomatic relief by infusing the treatment gas into a nasal and/or oral cavity without the patient necessarily inhaling the therapeutic gas. In particular, it has been found that by having the patient not inhale the therapeutic gas, i.e., substantially prevent passage of the therapeutic gas into the trachea or lungs by holding his or her breath or by breathing either nasally or orally via the route not being infused with the therapeutic gas, the volume of the body region being treated is significantly reduced. A relatively low volume of the carbon dioxide or other treatment gas can thereby be used to achieve the desired therapeutic effect. In addition, substantial exclusion from the lungs permits the use of the treatment gas at high (chronically unbreathable) concentrations, often being substantially pure approaching 100%, which is necessary to achieve maximum effective treatment via the nasal and oral mucosa. Furthermore, nasal or oral infusion of a chronically unbreathable mixture of an inert carrier gas with nitric oxide permits direct delivery of nitric oxide to the treated mucosa without the oxidation of nitric oxide that would occur if the carrier gas were a chronically breathable mixture of nitric oxide with air or oxygen.
In the case of mild headaches, rhinitis, or similar conditions, a total carbon dioxide volume as low as one cubic centimeter (cc) delivered over a time as short as one second may achieve adequate symptomatic relief. Of course, for more severe symptoms, such as those associated with migraine headache, the total treatment volumes of carbon dioxide and treatment times may be much greater.
Nasal and/or oral administration of concentrated carbon dioxide without inhalation may provide adequate symptom relief for asthma due to the physiologic phenomenon known as the nasobronchial reflex. In all cases, however, it is believed that the ability to successfully relieve the patient's symptoms depends primarily on the total volume of treatment gas delivered to the patient over a sufficiently long duration. That is, the rate at which the treatment gas is delivered has little effect, and generally the patient can use as rapid a delivery rate as the patient finds comfortable or tolerable in order to achieve a target total dosage and reduce the amount of time needed for treatment. Guidelines for dosages and treatment times for infusion into a nasal and/or oral cavity for common symptoms associated with particular ailments are set forth in the Dosage Guideline below.
The present invention also provides for the desired symptomatic relief of allergic eye irritation (e.g., conjunctivitis) by infusing the treatment gas over the eye, either behind a cupped hand over the eye or by other cup means that confine the therapeutic gas at high concentration over the eye for the treatment period. The treatment time and dose for treatment of the eye are similar to those for nasal and oral treatment.
A first aspect of the present invention provides methods for delivering a therapeutic gas, e.g., carbon dioxide, nitric oxide, oxygen, isocapnic mixtures of gaseous acids, helium, and the like to a human patient. The method comprises generating a flow of the carbon dioxide or other therapeutic gas, and infusing a mucous membrane or an eye with the flow of the gas. As described above, in order to limit and concentrate the infusion of the therapeutic gas for nasal and/or oral treatment, the patient usually refrains from inhaling the therapeutic gas while the nasal or oral mucous membrane is being infused or the patient breathes either nasally or orally via the route not being infused with the therapeutic gas. In this way, the volume of the nasal and/or oral cavity that is filled by the flowing therapeutic gas is minimized and the concentration of the gas maximized since the therapeutic gas does not need to fill the large capacity of the lungs to provide a therapeutic effect.
While it will be preferred not to inhale the therapeutic gas, the gases are not toxic and some passage of the gasses into the trachea and/or lungs will not significantly detract from the therapy. Moreover, with practice, many patients will be able to continue breathing ambient air through a nasal or oral route while simultaneously infusing the oral or nasal mucous membranes with the therapeutic gas. That is, in some cases, the patient may continue breathing through the mouth while infusing the nasal passages with the therapeutic gas or continue breathing through the nose while infusing the oral cavity with the therapeutic gas. Thus, in the first aspect of the present invention, the patient is required only to limit or inhibit passage of the therapeutic gas into the trachea and/or lungs in order to localize or concentrate the therapeutic gas in the nasal or oral passages being treated.
In particular embodiments, the therapeutic gas may comprise essentially pure carbon dioxide. By “essentially pure,” it is meant that the carbon dioxide, or other therapeutic gas, is free from the significant presence of other gases, i.e., the total volume of gas will comprise at least 50% carbon dioxide, preferably at least 70% carbon dioxide, and more preferably 95% or greater. In addition to being free from other gases, the carbon dioxide will be free from other physiologically or biologically active components, such as drugs, surfactants, and other substances that, although present at relatively low concentrations, would have physiologic or biologic effect.
In other embodiments, however, the carbon dioxide, or other therapeutic gas, may be present in a carrier which would have a significant presence, i.e., the total volume of carbon dioxide will comprise at least 6% carbon dioxide, preferably at least 30% carbon dioxide, and more preferably 49%. The carrier may be inert or biologically active. Exemplary inert carrier gases include nitrogen, air, oxygen, halogenated hydrocarbons, and the like. In preferred embodiments, the therapeutic gases are generated at a flow rate in the range from 1 cc/sec to 20 cc/sec, preferably from 2 cc/sec to 10 cc/sec. For pediatric application, flow rates less than 1 cc/sec (e.g., 0.5 cc/sec) may be preferred. Infusion preferably comprises directing the flow of therapeutic gas into one nostril and allowing the flow to infuse through the nasal passages and pass outwardly through the other nostril. Such infusion will occur under the pressure of the therapeutic gas that is being released into the one nostril, i.e., the patient is not inhaling or otherwise causing the therapeutic gas to infuse through the nasal passages. In such nasal passage infusion protocols, the patient's mouth is closed in order to block exit of the gas through the mouth. In an alternative infusion protocol, the therapeutic gas is directed into the patient's mouth and allowed to exit through either or both nostrils. In still another infusion protocol, the therapeutic gas is directed into a nostril or both nostrils and exits through the open mouth. In the latter two protocols, both the oral mucous membranes and nasal mucous membranes are infused with the therapeutic gas. The patient should avoid breathing substantially through the oral or nasal passages being perfused with the therapeutic gas. It should be recognized that the patient can breathe through the mouth while perfusing the nasal passages, and can breathe through the nose while perfusing the oral cavity. Furthermore, the patient can take single breaths during a long infusion step without substantially changing the total infusion time in that step.
The treatment steps may occur as a single infusion or multiple infusions. The length of any particular infusion step will depend, among other things, upon the degree of relief the patient is experiencing, i.e., the patient may continue and/or repeat infusions until relief is achieved. Single infusion steps usually will be performed for a time in the range from 1 second to 20 seconds for rhinitis relief and 1 second to 60 seconds for headache relief, and more usually from 2 seconds to 15 seconds for rhinitis and 10 seconds to 30 seconds for headache. The infusing steps often will be repeated one, two, three, four, or more times in order to achieve the desired total treatment time set forth in the table above. Usually, methods will be performed with hand-held or other delivery devices which have an adjustable flow rate capability. That is, the devices may be adjusted to deliver relatively constant therapeutic gas flows at a particular value within the range from 1 cc/sec to 20 cc/sec. The methods may thus further comprise adjusting the gas flow to a level which the patient perceives is comfortable. After the gas flow is adjusted, a total duration of treatment may be determined based on the gas flow and the desired total amount of gas to be delivered. While such treatment flows and treatment times may initially be selected based on data, such as provided in Table I above, it will be appreciated that the patient will eventually learn what treatment flow rates, treatment times, and number of treatments lead to successful symptom relief for them personally. Indeed, in medical practice today, gas therapy is a “titrate to effect” therapy without a specified dosage.
A second aspect of the present invention comprises methods for generating a therapeutic dosage of carbon dioxide or other treatment gas. The methods comprise releasing from a hand-held dispenser a flow of therapeutic gas comprising from 1 cc/sec to 20 cc/sec of carbon dioxide. Preferably, the gas flow will consist essentially of carbon dioxide, i.e., be pure carbon dioxide as described above. Alternatively, however, the gas flow may comprise carbon dioxide present in a carrier gas, also as described above and/or with solid or liquid drugs or other substances. The hand-held dispenser will have an outlet suitable for delivering the gas to the patient. In a preferred embodiment, the outlet will be suitable for sealing in or against a human nostril. In an alternative embodiment, the outlet will be suitable for sealing in or against a human mouth. In another alternative embodiment, the outlet will be suitable for sealing around a human eye or both eyes. One or more treatment steps may be performed, with each step having a duration in the range from 1 second to 100 seconds, preferably from 2 seconds to 30 seconds, and often from 1 second to 20 seconds, depending on the condition being treated and on its severity. The total number of treatment steps will be selected depending on symptom severity. Typically mild symptoms require 1 or 2 treatment steps, moderate symptoms require 2 to 3 treatment steps, and severe symptoms require 3 to 8 treatment steps. The total number of treatment steps will be selected depending on the flow rate in order to provide a total target dosage of the carbon dioxide. Typically, the flow rates will be adjustable to a set point within the range from 1 cc/sec to 20 cc/sec. While such treatment flows and treatment times and number of treatment steps may initially be selected based on data, such as provided in Table I above, it will be appreciated that the patient will eventually learn the treatment regimen that leads to successful symptom relief for them personally.
In yet another aspect, the present invention comprises dispensers for delivering therapeutic gases to a patient. The dispensers comprise a container holding a volume of the therapeutic gas, typically carbon dioxide or any of the other therapeutic gases described above. The dispenser further comprises a flow regulator that releases a flow of the therapeutic gas from the container to an outlet that is adapted to seal against a human nostril, mouth, or eye. Thus, the dispensers will be useful for delivering the therapeutic gas to the nostril, mouth, or eye for infusion of a mucous membrane according to the methods generally described above. As in the methods described above, the therapeutic gas is preferably carbon dioxide, either substantially pure carbon dioxide or carbon dioxide present in a carrier gas or liquid and/or combined with other active or non-active substances. The flow regulator preferably will be adjustable so that the patient can select a flow rate in the range from 1 cc/sec to 20 cc/sec, or within the other ranges set forth above. In an exemplary embodiment of the dispenser, the container comprises a cylinder, the adjustable flow regulator comprises a turnable cap at one end of the cylinder, and the outlet comprises a nozzle in the cap. The regulator may be turned to open the dispenser and initiate a flow of the carbon dioxide or other therapeutic gas. By then appropriately turning the cap, the flow rate can be adjusted to the user's preferred rate, and the outlet then inserted into or around the appropriate patient's orifice, in order to initiate infusion according to the methods described above.
In a further aspect, dispensers of the present invention for delivering carbon dioxide to a patient comprise a container holding a volume of carbon dioxide under pressure. A flow regulator is provided on the container and releases a flow of carbon dioxide from the container at a rate in the range from 1 cc/sec to 20 cc/sec. Preferably, the dispenser further comprises an outlet, where the outlet may be adapted to seal against a human orifice. Usually, the carbon dioxide will be substantially pure, although in other cases may be present in a carrier gas or liquid or in combination with other active or non-active substances. In certain particular embodiments, the carbon dioxide is present in the container as a liquid, wherein relatively large volumes of carbon dioxide can be stored. In other instances, the carbon dioxide will be present in the container as a pressurized gas. While the latter dispensers will hold less carbon dioxide, they do not need to be as sturdy as the containers that hold liquid carbon dioxide at much higher pressures. Preferably, the flow regulators will be adjustable to set points within the flow rate range.
In yet another aspect, kits according to the present invention comprise a container holding a therapeutic gas and instructions for use setting forth any of the methods described above for delivering the gas to a patient. The container may comprise any of the preferred dispensers described above, and the instructions for use and container will usually be packaged together in a conventional medical device package, such as a tube, tray, pouch, box, or the like.
1. Treatment of Allergic Rhinitis and Headache. It has been found by the inventors, that bathing the mucous membrane of the nose, nasal passages, and mouth, with gaseous carbon dioxide for times as short as one second can suppress the onset of acute irritation of the mucosa caused by triggers such as airborne and contact-transmitted allergens and/or antigens. Furthermore, chronic inflammation of the mucosa and associated distress, caused by extended exposure to allergens and/or antigens, may be relieved within a few minutes by repeating such carbon dioxide applications. A possible mechanism of action of the above described local carbon dioxide treatment is the following. Creating a high concentration of carbon dioxide (hypercapnia) by infusing it into the nasal passages causes a very fast lowering of the pH (making more acidic) of the mucous membranes depressing the neuronal activity (inhibiting inflammatory mediator release such as histamine) of the nerves that supply the nasal mucous membranes and connect directly to the brainstem. Asthma is known to be a comorbid disease to allergic rhinitis. Carbon dioxide is known to relax both central and peripheral airways in asthmatic adults. In addition, it is known that oxygenation is improved in patients with status asthmaticus, chronic obstructive pulmonary disease, and bronchiolitis by inhalation of helium. Also, inhaled nitric oxide improves the oxygenation and ventilation of most children with acute, hypoxic respiratory failure. For this reason, these respiratory ailments can be reduced or relieved by administering the above-described treatment using carbon dioxide or helium or nitric oxide. Furthermore, headaches (e.g., migraine headaches, tension-type headaches, cluster headaches, jaw pain, facial pain) are thought to be due to triggers creating a hyperexcitability state of nerves releasing inflammatory mediators such as histamine and serotonin. For this reason, headaches can be reduced or relieved by administering the above-described carbon dioxide treatment. Epilepsy, also a nervous hyperexcitability state, is known to be a comorbid disease to headaches and antiepileptic medications are used for migraine prevention. For this reason, epilepsy can be reduced or relieved by administering the above-described carbon dioxide treatment. A convenient hand-held easily controlled dispenser of carbon dioxide has been found to be an adequate and optimum means for practicing this carbon dioxide application process. Furthermore, other gases such as nitric oxide, oxygen, helium, and others may be administered similarly as therapeutic gases via the convenient hand-held easily controlled dispenser.
Essential elements of successful suppression of irritating symptoms, pain, and inflammation through use of carbon dioxide are the convenient dispensing of the carbon dioxide or other therapeutic gas at a time, at a controlled flow rate, and for a duration selected by the user. Because of the ability of carbon dioxide to quickly or immediately suppress an acute attack, the means for carbon dioxide application should be available immediately, upon demand by the user, at the time when irritating symptoms appear upon exposure to a trigger. If circumstances do not permit such immediate application, the means for application must be available continuously to relieve the consequent inflammation and distress as soon as possible after the exposure when circumstances permit its use.
Furthermore, it is desirable that the user be able to conveniently but precisely and controllably select a rate and duration of carbon dioxide flow that lies between the lower limit of effectiveness and the upper limit of tolerance. It has been found that these limits are subjective, depending upon the personal sensitivities of the individual user, the degree and extent of the user's irritant reaction, and the site of carbon dioxide injection. Flows as low as 1 cc/sec for 1-2 seconds into the nose are effective for suppression of onset of acute allergic symptoms, whereas flows of 4-5 cc/sec for 5-10 seconds are typically selected for optimum relief from a mild chronic allergy attack. For severely inflamed mucosa and/or for injection into the mouth, flows as high as 10 cc/sec or higher for as long as 15 seconds or longer often are selected for optimum relief. For the treatment of tension and migraine headaches, the flow durations can be substantially longer, as generally set forth in the Dosage Guideline (Table I) above.
At low flow rates, the presence of the carbon dioxide produces a “tingling” sensation similar to that produced during drinking of carbonated beverages that inadvertently enter the nasal passages e.g., “bubbles up the nose”. This is the effective rate and the tingling is a welcome sensation because it usually coincides with immediate relief of symptoms. Above a certain subjectively determined flow rate the sensation becomes unpleasant, which may be described as a “stinging” or “burning” sensation. At a still higher flow rate (maximum tolerable rate), the stinging sensation becomes intolerable and subjects remove the device from their nostril. It has been found that, for a few individuals, this tolerance level can be as low as 1-2 cc/sec for a second or less of injection into the nose. More typically, an injection rate of up to 10 cc/sec can be tolerated for 5 seconds or more into the nose by most users and into the mouth by almost all users. It must be noted, however, that the tolerance level depends strongly on the sequential phase of the application and on the degree of inflammation and/or pain at that phase. The tolerance level generally is lower (e.g., <3 cc/sec typically) at the onset of the first carbon dioxide injection, especially when there has been chronic inflammation and/or pain. After a few seconds the tolerance level rises substantially to the levels already discussed. In fact, the “stinging” sensation is described as a welcome immediate relief to the “tickling” sensation that causes sneezing and other distress during an allergy attack, i.e., analogous to relieving an itch by scratching a skin irritation. Similarly, the “stinging” sensation is described as a welcome immediate relief to the “pressure” sensation that causes pain and other distress during a headache attack.
Accordingly, the range of effective and tolerable flow rates of carbon dioxide is between 1 cc/sec and 20 cc/sec, preferably between 1 cc/sec and 10 cc/sec, and most preferably between 2 cc/sec and 10 cc/sec. The carbon dioxide flow is preferably regulated easily, controllably, and with rapid response within this range of flow rates by the user.
Most often the major site of general distress is the head, for which the preferred mode of carbon dioxide injection is directly into a nostril. While not inhaling the carbon dioxide, carbon dioxide is injected into a nostril and continued until full relief is obtained. This usually occurs when the carbon dioxide flow is detected exiting the opposite nostril and/or the mouth. With an allergy attack, often the nasal passages are blocked by swelling of the mucosa, in which case sufficient pressure automatically builds to open and perfuse the passage through each nostril separately. When both passages are clear, each can be perfused separately by holding one nostril closed while opening the mouth, or both can be perfused by closing the mouth and allowing the flow into one nostril to exit through the other. Frequently inflammation, swelling, and itching of the upper mouth accompany the irritant reaction to the allergen and/or antigen. In this case, it is most effective to inject the carbon dioxide through pursed lips directly into the mouth with exit through the nose while the breath is held. Specific techniques may be learned by experience and optimum procedures will depend on personal preference. The ability of the patient to optimize the treatment protocol is enabled by the fully adjustable flow rate and selectable injection site afforded by the devices of the present invention.
2. Initial Dispenser Embodiment.
The configuration of the initial dispenser embodiment as shown in
It has been found that mounting the needle 18 in a head 16 material with a relatively high degree of elasticity, such as a plastic polymer, provides a degree of compliance sufficient to accommodate any off-axis “wobble” that occurs during rotation of the head and thereby avoids the associated non-circular and leaky penetration hole that occurs when the needle is mounted rigidly in a metal head. The elastic mount also provides compressive compliance that keeps the needle firmly seated after its repeated insertion into the orifice.
The configuration of the dispenser embodiment shown in
The dispenser 10 can be conveniently operated using the steps illustrated in
Referring now to
It should be apparent that methods other than rotation of the dispenser head can be used to controllably vary the flow through a perforation orifice; e.g., the needle can be moved axially by a lever arrangement to controllably accomplish the described perforation and flow regulation within the preferred range of flow rates described herein. Such an arrangement in a hand-held embodiment having a similar optimum degree of sensitivity and range of adjustment by the fingers as the rotation means described herein can achieve the same result.
3. Embodiment with Separate Puncture and Flow Control Means. Referring now to
Flow regulation in the dispenser head 80 is provided by the second tapered region 102 which is received in a valve seat 104 formed in the upper end of the lower collar 87. Rather than relying on needle penetration to form the flow control aperture, dispenser head 80 relies on a pre-formed conical valve seat 104 which mates with the tapered region 102 on the needle. In this way, the dimensions of both the seat 104 and the tapered region 102 may be carefully controlled in order to assure accurate gas flow control. Thus, when the flow regulating cap 84 is twisted to raise the cap relative to lower collar 82, the tapered region 102 will be lifted out of the valve seat 104. In this way, the flow regulation of the gas can be controlled. Additionally, sealing of the gas flow when the cartridge is to be turned off is provided by both seating of the tapered needle portion 102 in the seat 104 as well as seating of the needle tip in the penetration created in the seal 90. The use of the valve seat 90, which can be formed from a conventional hard metal, ceramic, or other valve material, can greatly enhance the useful life of the dispenser head 80. Thus, such designs may be particularly valuable for non-disposable units where the dispenser head 80 can be reused. Of course, the associated gas cartridge will be replaced whenever the gas being carried has been depleted.
4. Preferred Dispenser Embodiment. From the tests with the initial dispenser embodiment, several improvements were defined leading to a preferred embodiment that also was constructed and tested. It was found that the preferred dispensers of the present invention should enable precise but easy control of the flow rate over the desired flow ranges in a convenient hand-held configuration. In the specific preferred embodiment illustrated in
Specifically, it has been found that the rotation of the dispenser head of the preferred embodiment required to obtain the maximum flow rate employed by most users, e.g., 10 cc/sec, should not and need not exceed about 120 degrees in order to obtain an entirely adequate sensitivity of adjustment and to not exceed the rotation comfortably obtainable with a continuous motion of the thumb and index finger. Conversely, a degree of rotation to obtain such typical maximum flow rate, if less than about 30 degrees, is too coarse for sensitive adjustment of the flow over the 1-10 cc/sec range of typical optimum flow rates defined previously. It should be apparent that the optimum relationship between flow rate and degree of head rotation can be obtained by selecting appropriate combinations of perforation orifice size, head diameter and fineness of threads on the cartridge (number of threads/inch).
In using the needle having the initial configuration shown in
The preferred dispenser embodiment shown in
The preferred needle configuration, shown in
As shown analytically in
Accordingly, exemplary dimensions for the needles 18 and 18′ and cap 30 are set forth in Table II below and provide for desired flow rates in the range from 1 cc/sec to 20 cc/sec for cartridges 12 holding liquid carbon dioxide under pressure. It should be apparent that the preferred needle configuration shown in
5. Embodiment with Separate Puncture and Valve Seal Mechanism. Referring now to
Flow regulation in the dispenser head 80 is provided by the second tapered region 102 which is received in a valve seat 104 formed in the upper end of the lower collar 87. Rather than relying on needle penetration to form the flow control aperture, dispenser head 80 relies on a pre-formed conical valve seat 104 which mates with the tapered region 102 on the needle. In this way, the dimensions of both the seat 104 and the tapered region 102 may be carefully controlled in order to assure accurate gas flow control. Thus, when the flow regulating cap 84 is twisted to raise the cap relative to lower collar 82, the tapered region 102 will be lifted out of the valve seat 104. In this way, the flow regulation of the gas can be controlled. Additionally, sealing of the gas flow when the cartridge is to be turned off is provided by both seating of the tapered needle portion 102 in the seat 104 as well as seating of the needle tip in the penetration created in the seal 90. The use of the valve seat 90, which can be formed from a conventional hard metal, ceramic, or other valve material, can greatly enhance the useful life of the dispenser head 80. Thus, such designs may be particularly valuable for non-disposable units where the dispenser head 80 can be reused. Of course, the associated gas cartridge will be replaced whenever the gas being carried has been depleted.
6. Alternative Gas Provision Means. Referring now to
As described thus far, the embodiments of the dispensers of the present invention have relied on high pressure systems which contain liquid carbon dioxide or other therapeutic gas. Low pressure systems may be assembled in at least two ways. As shown in
7. Description of Use of the Dispenser Embodiments. Referring now to
In other embodiments, the user may place the cartridge 10 into his/her mouth, permitting the carbon dioxide or other therapeutic gas to infuse upwardly through the throat and outward through the nostrils. Again, the patient will generally refrain from inhaling the therapeutic gas so that the treatment gas does not enter into the trachea or lungs. By limiting the regions being treated to the nasal passages and in some instances the nasal passages and upper regions of the throat, only very small volumes of the gas are required for treatment, and high (unbreathable) concentrations of the gas can be more effectively employed. This is particularly advantageous when hand-held systems are used where the amount of carbon dioxide or other treatment gas is limited. As noted in the examples provided below, it has been found that even very low volumes of carbon dioxide can be highly effective in treating a number of symptoms associated with the common ailments described above.
As shown in
The following examples are offered by way of illustration, not by way of limitation.
EXPERIMENTAL 1. Dispenser Models Constructed and TestedTwo models of the initial one-piece head embodiment shown in
A. Materials and Methods
Test Device
The test device was a hand-held, multi-dose, disposable, dispenser that was approximately 3 to 4 inches long and 6/8 to ⅞ inches in diameter constructed as described above. The device consisted of a plastic twist-top flow regulator mounted on top of a pressurized steel cartridge containing liquid carbon dioxide. The tip of the flow regulator has a nosepiece that is the optimal size and configuration to place against and seal off a nostril for administration of the gas. In a number of subjects, the effective nasal and oral carbon dioxide flow rates, and maximum tolerable nasal and oral flow rates, were measured using a laboratory apparatus. This apparatus consisted of a flow regulator connected via tubing to a flow meter and a large tank of carbon dioxide. These flow data were used, together with the number of seconds gas was administered during therapy, to calculate the estimated dose of gas in milliliters.
Subjects
Of the total of 15 subjects included in the analysis, 11 used the treatment for 35 headaches and 9 subjects used it for 9 allergy attacks. Three subjects treated both headache and allergy but on different days. The subjects included adults, elderly, and children of both sexes in good general health, having mild, moderate, and severe headaches or having allergies to plant, animal, or airborne allergens. The device was used to treat migraine and tension-type headaches, jaw pain, and allergies (allergic rhinitis, with symptoms that included sinus congestion, sneezing, and itchy throat and eyes). There was no limitation on the duration of symptoms before treatment with the device. Subjects with no prior use of the device and those who have used it (to treat allergy symptoms) previously were included.
Transmucosal Treatment
Carbon dioxide (100%) was administered nasally by the subject for a few seconds via a nostril to fill the nasal passages while holding their breath, or taking breaths of room air occasionally if the dose was lengthy. The gas exited the other nostril. Such nasal administration is similar to presently marketed nasal inhalers except that the administered gas was not inhaled. Oral administration, via pursed lips with carbon dioxide exiting via the nostrils, was found to be more effective for allergic inflammation extending into the oral cavity. Subjects took as many doses as they needed for relief. It is important to note that there were no number of doses, duration of dose, time between doses, or gas flow rate specified for the user. Subjects chose their own regimen for symptom relief. Similarly, in medical practice today, gas therapy is a “titrate to effect” therapy without a specified dosage.
Outcome Measures
The International Headache Society (IHS) divides headache intensity into three categories: mild, moderate, and severe. The rating of the intensity level depends on the extent to which the headache interferes with the ability to function. Mild headaches do not interfere with the ability to function, moderate headaches interfere with the ability to function but do not require bed rest, and severe headaches are incapacitating and require bed rest. The IHS uses headache relief at two hours as its primary outcome measure for present-day headache drug studies. Since therapy of the present invention acts much faster than present-day drugs, the primary outcome measure selected for this analysis was headache relief at 30 minutes. Each of the headache outcome measures used for this analysis is as follows:
-
- Headache relief efficacy at 1, 5, 15, and 30 minutes post-treatment—headache relief efficacy is obtained when a pre-treatment headache severity of mild, moderate, or severe severity is improved to a post-treatment severity of none, mild, or moderate respectively.
- Headache free efficacy at 1, 5, 15, and 30 minutes post-treatment—headache free efficacy is obtained when a pre-treatment headache of mild, moderate, or severe severity is improved to a post-treatment severity of none.
- Headache recurrence within 24 hours post-treatment—recurrence within 24 hours is defined as no or mild headache severity after treatment that then worsened to moderate or severe headache severity within 24 hours after treatment with no use of rescue medication before the worsening.
- Safety parameter—safety is defined as no adverse after-effects of treatment.
For allergy, the rating of the intensity level depends on the extent to which the allergy interferes with the ability to function. Mild allergies do not interfere with the ability to function, moderate allergies interfere with the ability to function but do not completely disrupt the function, and severe allergies are incapacitating and completely disrupt the ability to function. The same outcome measures as for headache were used for allergy.
B. Results and Discussion
Dosage
Initially, the effective nasal and oral, and maximum tolerable nasal and oral carbon dioxide flow rates were measured in seven subjects using a laboratory apparatus. The flow rate selected that is effective or the maximum tolerable rate varies with the individual. At low flow rates, the presence of the carbon dioxide produces a “tingling” sensation similar to that produced during drinking of carbonated beverages that inadvertently enter the nasal passages e.g., “bubbles up the nose”. This is the effective rate and the tingling is a welcome sensation because it usually coincides with immediate relief of symptoms. Above a certain subjectively determined flow rate the sensation becomes unpleasant, which may be described as a “stinging” or “burning” sensation. At a still higher flow rate (maximum tolerable rate), the stinging sensation becomes intolerable and subjects remove the device from their nostril. Also, subjects are more sensitive to the first dose of a series for one attack; subsequent doses give less or no sensation. The flow data show that lower effective and maximum tolerable flow rates were selected by subjects having no prior experience with the treatment (see Table III below). High flow rates were better tolerated orally than nasally. The typical effective rate nasally was 1 to 5 ml/sec and 5 to 10 ml/sec orally.
For therapy, it is important to note that no number of doses, duration of dose, time between doses, or gas flow rates were specified for the user. Subjects chose their own regimen for symptom relief. Analysis of the therapy data (see Table IV below) shows that the treatment is dose dependent. In general, milder attacks required fewer doses of shorter duration, thus a lower volume of gas, than severe attacks. Also, tension-type headaches required shorter average duration doses than migraine headaches (tension=24 sec, range=6-56 sec; migraine=57 sec, range=30-83 sec), and generally a lower volume of gas (tension=122 ml, range=28-288 ml; migraine=158 ml, range=82-233 ml). The average duration and total dose volume for headache and allergy treatment were similar (headache=32 sec and 124 ml; allergy=39 sec and 133 ml) as were the total treatment times (headache=7 min; allergy=−5 min).
Headache
A total of 11 headache subjects with 35 headaches were assessed. The subjects were males (49%) and females (51%) ranging in age from 9 to 73 years (mean=55) with mild (26%), moderate (43%), and severe (31%) headaches which included migraine (29%), tension-type (66%), and jaw headaches (5%). Headache duration before treatment averaged 2 hours (migraine=2.4 hours, tension=1.5 hours) and ranged from 0.3 to greater than 18 hours for migraines and 0.1 to 4 hours for tension-type headaches. The subjects with migraines had used the device from 0 to 8 times and those with tension-type headache from 0 to 13 times with one individual who had not used it previously for headache but has used it for allergies over 1000 times.
Using the efficacy outcome measures defined above, (which include mild headaches, with relief defined as mild, moderate, or severe reduced to none, mild, or moderate respectively) the present treatment had a 94% headache relief efficacy (migraine=90%, tension=96%) and an 80% headache free efficacy (migraine=90%, tension=80%) for headaches at 30 minutes post-treatment (see Table V below). Considerable headache relief was also obtained at 15 minutes post-treatment (headache relief efficacy=86%; headache free efficacy=74%). Subjects reported immediate onset of symptom relief within seconds while administering the first dose. There were no instances of headache recurrence 24 hours post-treatment with the gas therapy and no subjects reported any adverse after effects of treatment.
Using the more stringent IHS efficacy outcome measures (that exclude mild headaches, with relief defined as moderate or severe reduced to mild or none) the treatment had the same average symptom headache free efficacy of 80% (migraine=75%, tension=80%) for headache at 30 minutes as in the above analysis (see Table VI below).
With these criteria, the treatment had an 84% headache relief efficacy (migraine=100%, tension=77%) for headache at 30 minutes. Considerable headache relief also was obtained at 15 minutes post-treatment (headache relief efficacy=72%; headache free efficacy=72%).
In summary, treatment of migraine and tension-type headache according to the present invention shows 80-94% efficacy occurring in seconds to minutes (average treatment time=−7 min) compared to 50-70% efficacy in 2-4 hours with current drugs even though this was a dose-finding analysis where the optimal dosing regimen was not defined. This feasibility summary had many subjects who had never used the device, or never used it for headaches, resulting in a number of instances where therapy was more efficacious after they learned the most effective personal dosing regimen. For example, a subject suffering severe tension headaches tried on three occasions to eliminate the headaches with only moderate success using numerous doses of short duration (six doses of 8 sec each=240 ml). Subsequently, she was able to completely eliminate a severe tension headache and a severe jaw/tooth ache with fewer doses of longer duration (three doses of 15 sec each=225 ml and three doses of 45 sec each=675 ml, respectively). As another example, a subject suffering a moderate tension headache, who had never used the device for headaches, tried to eliminate the headache with no success using an extremely small dose (one dose of 1 sec=2 ml). Finally, one patient suffering from a migraine headache was unable to improve on a mild migraine the first time he used the device (one dose for 30 sec=60 ml). However, he was able to completely eliminate all subsequent mild and severe migraines with a dosage regimen he developed that increased the gas volume dose (two to three doses for 25 sec each=120 ml). He had a history of severe migraines bimonthly for over 25 years and had selected sumatriptan (Imitrex®) by injection as a treatment prior to receiving the device. Since he has tested the device of the present invention, he has used no other headache medication and no longer has moderate or severe migraines. When he first feels the onset of a migraine, he doses twice for 20 to 25 seconds according to the present invention. This completely aborts the migraine and it does not recur. The frequency of migraine incidents has also decreased.
Allergy
There were 9 allergy subjects with 9 allergy attacks assessed. The subjects were males (67%) and (33%) females ranging in age from 9 to 72 years (mean=39) with mild (11%), moderate (22%), and severe (67%) allergies which included symptoms in the nose, throat, and eyes). Allergy duration before treatment ranged from 0.2 to 1.5 hours. The subjects had used the device from 0 to over 1000 times.
The treatment achieved 100% allergy relief efficacy and an 89% allergy free efficacy at both 15 and at 30 minutes (see Table VII below). Using the more stringent efficacy outcome measures (which exclude mild allergies and relief is defined as moderate or severe reduced to mild or none) the treatment had essentially the same allergy relief efficacy and allergy free efficacy as in the above analysis. Subjects reported immediate onset of symptom relief within seconds while administering the first dose. There was a 50% recurrence of allergy symptoms; however, N was small (N=4) for this determination. The recurrences did not occur until 3 hours or longer post-treatment.
In summary, treatment of allergic rhinitis according to the present invention shows 88-100% efficacy occurring in seconds to minutes (average treatment time=5 min) compared to minutes to hours with current drugs. No subjects reported any adverse after effects of treatment.
While the above is a complete description of the preferred embodiments of the invention, various alternatives, modifications, and equivalents may be used. Therefore, the above description should not be taken as limiting the scope of the invention that is defined by the appended claims.
Claims
1-10. (canceled)
11. A device for treating rhinitis or conjunctivitis comprising:
- a hand-held, multi-dose dispenser, the dispenser comprising a carbon dioxide cartridge having a therapeutic dosage of carbon dioxide therein, a nosepiece, and a flow regulator, the flow regulator comprising a flow-controlling orifice, the flow regulator configured to repeatedly control the flow of carbon dioxide from the cartridge at a rate from 1 cc/sec to 20 cc/sec.
12. The device of claim 11, wherein the dispenser is a two-piece dispenser.
13. The device of claim 11, wherein the dispenser is a one-piece dispenser.
14. The device of claim 11, further comprising a pressure regulator.
15. The device of claim 11, wherein the gas comprises at least 50% carbon dioxide.
16. The device of claim 11, wherein the gas comprises at least 70% carbon dioxide.
17. The device of claim 11, wherein the gas comprises at least 95% carbon dioxide.
18. The device of claim 11, wherein the gas comprises substantially pure carbon dioxide.
19. The device of claim 11, further comprising a seal adjacent to the carbon dioxide cartridge.
20. The device of claim 11, further comprising a needle configured to pierce the carbon dioxide cartridge.
21. The device of claim 11, wherein the nosepiece is rotatable.
22. The device of claim 11, wherein the nosepiece, cartridge, and flow regulator, are in axial alignment.
23. The device of claim 11, wherein the nosepiece is tapered.
24. The device of claim 11, wherein the flow rate is selectable by a user of the device.
25. The device of claim 11, wherein the cartridge is replaceable.
26. The device of claim 11, wherein the therapeutic dosage is accomplished at a duration of 2-30 seconds per nostril.
Type: Application
Filed: Oct 28, 2010
Publication Date: Feb 17, 2011
Applicant: Capnia, Inc. (Palo Alto, CA)
Inventors: Ned S. RASOR (Cupertino, CA), Julia S. Rasor (Los Gatos, CA)
Application Number: 12/914,847
International Classification: A61M 37/00 (20060101);
