ABSTRACT
Solid oral dosage forms can be divided into two main categories: immediate-release dosage forms, where disintegration and subsequent drug release and dissolution occurs in the stomach and the modified-release technologies. Post-gastric-emptying, single-unit systems generally move through the small intestine intact, whereas multiple-unit systems spread out as discrete units. Capsules are used as an alternative to tablets, for poorly compressible materials, to mask the bitter taste of certain drugs, or sometimes to increase bioavailability. Many of the polymeric excipients used to “bulk out” capsule fills are the same as those used in immediate-release tablets. The therapeutic effect of drugs that have a short biological half-life may be enhanced by formulating them as extended- or sustained-release dosage forms. Extended- and sustained-release dosage forms prolong the time that systemic drug levels are within the therapeutic range and, thus, reduce the number of doses the patient must take to maintain a therapeutic effect, thereby increasing compliance.
