Abstract: Bioadhesives coatings increase the gastrointestinal retention time of orally-ingested medicaments. Certain bioadhesive coatings producing a fracture strength of at least 100 N/m2, as measured on rat intestine, when applied to at least one surface of a pharmaceutical dosage form for oral delivery of a drug, result in a gastrointestinal retention time of at least 4 hours in a fed beagle dog model, during which the drug is released from the dosage form. Multi-layer tablets, particularly those including hydrophobic excipients, are useful in administering hygroscopic and/or deliquescent drugs. In addition, varying the amount of drug in multi-layer tablets allows the release rate of the drug to be controlled.

Abstract: Bioactive agents may be reproducibly converted into particles having diameters in the range of about 5 to about 2000 nanometers (nm). Conversion is accomplished by dissolving the bioactive agent in a solvent for the bioactive agent, and rapidly altering the polarity of the solution to make it a non-solvent for the bioactive agent, for example by diluting the bioactive agent solution with an excess of a liquid that is a non-solvent for the bioactive agent but is miscible with the solvent. Precipitated bioactive agent nanoparticles are collected by centrifugation, filtration or lyophilization. The nanoparticles have a relatively narrow size distribution, and the average diameter can be controlled by choice of solvent and non-solvent. The nanoparticles are typically amorphous. A surfactant may be added to ensure dispersion of the particles when administered. In the preferred embodiment, the bioactive agent is a drug with low aqueous solubility.