Abstract: Provided is a method of treating a patient suffering from a pain state by administering to the patient a gastric retentive dosage form of gabapentin that is capable of administration in once-daily or twice daily dosing regimens. By reducing the need to administer gabapentin from the thrice-daily administrations characteristic of immediate release gabapentin, the gastric retentive gabapentin dosage forms provided herein have the advantages of improving patient compliance for gabapentin treatment. In addition to the foregoing, the gastric retentive gabapentin dosages forms also exhibit decreased blood plasma concentrations and increased bioavailability throughout the dosing regimen.

Abstract: Provided is a method of treating a patient suffering from a pain state by administering to the patient a gastric retentive dosage form of gabapentin that is capable of administration in once-daily or twice daily dosing regimens. By reducing the need to administer gabapentin from the thrice-daily administrations characteristic of immediate release gabapentin, the gastric retentive gabapentin dosage forms provided herein have the advantages of improving patient compliance for gabapentin treatment. In addition to the foregoing, the gastric retentive gabapentin dosages forms also exhibit decreased blood plasma concentrations and increased bioavailability throughout the dosing regimen.

Abstract: Drug tablets that include a prolonged-release core and an immediate-release layer or shell are prepared with a thin barrier layer of drug-free polymer between the prolonged-release and immediate-release portions of the tablet. The barrier layer is penetrable by gastrointestinal fluid, thereby providing full access of the gastrointestinal fluid to the prolonged-release core, but remains intact during the application of the immediate-release layer, substantially reducing or eliminating any penetration of the immediate-release drug into the prolonged-release portion.

Abstract: Unit dosage form tablets for the delivery of pharmaceuticals are formed of the pharmaceutical dispersed in a solid unitary matrix that is formed of a combination of poly(ethylene oxide) and hydroxypropyl methylcellulose. The combination offers unique benefits in terms of release rate control and reproducibility while allowing both swelling of the tablet to effect gastric retention and gradual disintegration of the tablet to clear the tablet from the gastrointestinal tract after release of the drug has occurred.

Abstract: A method is disclosed for manufacturing a pharmaceutical tablet for oral administration, the tablet combining both immediate-release and prolonged-release modes of drug delivery and using an immediate-release drug that is either insoluble in water or only sparingly soluble and is present in a very small amount compared to the prolonged-release drug. The method involves the use of particles of the immediate-release drug that are equal to or less than 10 microns in diameter, applied as a layer or coating over a core of the prolonged-release drug, the layer or coating being either the drug particles themselves, applied as an aqueous suspension, or a solid mixture containing the drug in admixture with a material that disintegrates rapidly in gastric fluid.

Abstract: Drugs are formulated as unit oral dosage forms by incorporating them into polymeric matrices comprised of hydrophilic polymers that swell upon imbibition of water to a size that is large enough to promote retention of the dosage form in the stomach during the fed mode. The oral formulation is designed for gastric retention and controlled delivery of an incorporated drug into the gastric cavity, and thus administered, the drug is released from the matrix into the gastric fluid by solution diffusion. The swollen polymeric matrix, having achieved sufficient size, remains in the gastric cavity for several hours if administered while the patient is in the fed mode, and remains intact long enough for substantially all of the drug to be released before substantial dissolution of the matrix occurs. The swelling matrix lowers the accessibility of the gastric fluid to the drug and thereby reduces the drug release rate.

Abstract: A method is disclosed for manufacturing a pharmaceutical tablet for oral administration, the tablet combining both immediate-release and prolonged-release modes of drug delivery and using an immediate-release drug that is either insoluble in water or only sparingly soluble and is present in a very small amount compared to the prolonged-release drug. The method involves the use of particles of the immediate-release drug that are equal to or less than 10 microns in diameter, applied as a layer or coating over a core of the prolonged-release drug, the layer or coating being either the drug particles themselves, applied as an aqueous suspension, or a solid mixture containing the drug in admixture with a material that disintegrates rapidly in gastric fluid.

Abstract: Drugs are formulated as oral dosage forms for controlled release in which the release rate limiting portion is a shell surrounding the drug-containing core. The shell releases drug from the core by permitting diffusion of the drug from the core. The shell also promotes gastric retention of the dosage form by swelling upon imbibition of gastric fluid to a size that is retained in the stomach during the postprandial or fed mode.

Abstract: Unit dosage form tablets for the delivery of pharmaceuticals are formed of the pharmaceutical dispersed in a solid unitary matrix that is formed of a combination of poly(ethylene oxide) and hydroxypropyl methylcellulose. The combination offers unique benefits in terms of release rate control and reproducibility while allowing both swelling of the tablet to effect gastric retention and gradual disintegration of the tablet to clear the tablet from the gastrointestinal tract after release of the drug has occurred.

Abstract: Drugs intended for absorption in the stomach or upper intestinal tract are administered in oral drug delivery systems in conjunction with any of various substances that have been discovered to function as potent agents for inducing the fed mode. By inducing the onset of the fed mode, these agents cause the stomach to prolong its retention of the drug delivery system, which is either large enough to be retained in the stomach during the fed mode or swells or expands to such a size upon ingestion. The fed mode inducing agents include the following compounds and their salts: glycine and glycylglycine, xylitol and related sugar alcohols, sodium and other metal docusates, &bgr;-casomorphins, &agr;-lipoic acid and similarly structured acids, 2,2-diaryl-4-(4′-aryl-4′-hydroxypipendino)butyramides, arginine, Trp-Trp, alkylpyridinium halides, dihydroxybenzoic acids, and potent sweeteners such as aspartame, aspartic acid, acesulfame, and stevioside.

Abstract: Drugs are formulated as unit oral dosage forms by incorporating them into polymeric matrices comprised of hydrophilic polymers that swell upon imbibition of water to a size that is large enough to promote retention of the dosage form in the stomach during the fed mode. The oral formulation is designed for gastric retention and controlled delivery of an incorporated drug into the gastric cavity, and thus administered, the drug is released from the matrix into the gastric fluid by solution diffusion. The swollen polymeric matrix, having achieved sufficient size, remains in the gastric cavity for several hours if administered while the patient is in the fed mode, and remains intact long enough for substantially all of the drug to be released before substantial dissolution of the matrix occurs. The swelling matrix lowers the accessibility of the gastric fluid to the drug and thereby reduces the drug release rate.

Abstract: The retention of oral drug dosage forms in the stomach is improved by using swellable dosage forms that are shaped in a manner that will prevent them from inadvertently passing through the pylorus as a result of being in a particular orientation. The planar projection of the shape is one that has two orthogonal axes of different lengths, the longer being short enough to permit easy swallowing prior to swelling while the shorter is long enough within one-half hour of swelling to prevent passage through the pylorus.

Abstract: Metformin is formulated as a pharmaceutical composition that also includes a 5-hydroxytryptamine-3 receptor antagonist to suppress the gastrointestinal side effects that are associated with metformin administration in many patients.

Abstract: Drugs are formulated as unit oral dosage forms by incorporating them into polymeric matrices comprised of hydrophilic polymers that swell upon imbibition of water to a size that is large enough to promote retention of the dosage form in the stomach during the fed mode. The oral formulation is designed for gastric retention and controlled delivery of an incorporated drug into the gastric cavity, and thus administered, the drug is released from the matrix into the gastric fluid by solution diffusion. The swollen polymeric matrix, having achieved sufficient size, remains in the gastric cavity for several hours if administered while the patient is in the fed mode, and remains intact long enough for substantially all of the drug to be released before substantial dissolution of the matrix occurs. The swelling matrix lowers the accessibility of the gastric fluid to the drug and thereby reduces the drug release rate.

Abstract: Drugs are formulated as unit oral dosage forms by incorporating them into polymeric matrices comprised of hydrophilic polymers that swell upon imbibition of water to a size that is large enough to promote retention of the dosage form in the stomach during the fed mode. The oral formulation is designed for gastric retention and controlled delivery of an incorporated drug into the gastric cavity, and thus administered, the drug is released from the matrix into the gastric fluid by solution diffusion. The swollen polymeric matrix, having achieved sufficient size, remains in the gastric cavity for several hours if administered while the patient is in the fed mode, and remains intact long enough for substantially all of the drug to be released before substantial dissolution of the matrix occurs. The swelling matrix lowers the accessibility of the gastric fluid to the drug and thereby reduces the drug release rate.

Abstract: Controlled-release oral drug dosage forms that comprise a tablet or capsule containing a plurality of particles of a solid-state drug dispersed in a swellable/erodible polymer, such as poly(ethylene oxide) are described. Once ingested, the tablet or capsule disintegrates to disperse the particles within the stomach where they imbibe water to cause them to swell and promote retention in fed-mode-induced patients. As the gastric-retained dosage form gradually erodes, the drug is released in a controlled manner to the stomach for treatment of local disorders, and to the upper gastrointestinal tract where it becomes available for absorption in a controlled and therapeutic manner. Drug-containing vesicles, such as liposomes or nanoparticles or enteric-coated drug particles, can also be delivered to the gastrointestinal tract in a controlled manner using the gastric-retentive dosage forms of the present invention.

Abstract: Sustained release oral drug dosage forms that comprise a tablet or capsule containing a plurality of particles of a solid-state drug dispersed in alkyl cellulose such as hydroxyethylcellulose or hydroxypropylcellulose. Once ingested the tablet or capsule disintegrates to disperse the particles into the stomach where they imbibe water to cause them to swell and also to become slippery, thus enhancing their retention in the stomach. Imbibed water from the gastric fluid dissolves the drug entrapped in the particles and the resulting solution diffuses from the dispersed particles, assuring that no solid drug, which with some drugs is more irritating, contacts the mucosal tissue. A number of embodiments of the dosage form utilizing different drugs are exemplified and the benefits are explained. Aspirin is one example.