Extended release formulation contg. venlafaxin

Abstract

This invention relates to a 24 hour extended release dosage formulation and unit dosage form thereof of venlafaxine hydrochloride, and antidepressant, which provides better control of blood plasma levels than conventional tablet formulations which must be administered two or more times a day and further provides a lower incidence of nausea and vomiting than the conventional tablets. In its primary aspect, this invention provides an improved core of the extended release spheroids comprised of venlafaxine hydrochloride and microcrystalline cellulose, that is, without the addition of hydroxypropylmethylcellulose.

Description

Background of the invention [0001] Sustained release pharmaceutical formulations are usually made as compressed tablets using hydrogel tablet technology. To manufacture these sustained-release tablet dosage forms, the active ingredient is usually combined with a cellulose ether (such as methylcellulose, ethylcellulose or hydroxypropylmethylcellulose) with or without other excipients. element) were mixed and the resulting mixture was compressed into tablets. When these tablets are taken orally, the cellulose ether in the tablet swells when hydrated by moisture in the digestive system, thereby limiting the active ingredient's exposure to moisture. As the cellulose ether is gradually leached out by the water, which penetrates deeper into the gel matrix, the active ingredient slowly dissolves and diffuses through the gel, allowing it to be absorbed by the body. U.S. Patent 4,966,768 has analgesic / anti-inflammatory drug itodolac (Lodine  ) is an example of such a sustained rele...

AI Technical Summary

Problems solved by technology

Heat build-up occurs during extrusion, which dries the extrudate so much that it is difficult to convert the extruded cylinder into pellets