Drug-release systems, oral

Oral controlled drug-release systems are increasingly used for short half-life drugs to reduce peak blood levels and side-eflfects, to maintain optimum drug concentration and to stimulate patient compliance. In order to maintain a constant blood-level of the drug during an extended period, a constant in vitro drug release rate is desired. The most popular controlled-release system is the matrix tablet (Desai et al., 1965). Te Wierik et al. (1996) reported on... 

Chitosan has been widely used as matrix in drug-release systems in the form of beads and granules, as promising vehicles for oral drug sustained-release formulations [164]. 

Kostova B, Momekova D, Petrov P, Momekov G, Toncheva-Moncheva N, Tsvetanov CB, Lambov N (2011) Poly(ethoxytriethylene glycol acrylate) cryogels as novel sustained drug release systems for oral application. Polymer 52 1217-1222... 

Waiver of in vivo bioavailability and bioequivalence studies for immediate release solid oral dosage forms based on a biopharmaceutics classification system. Center for Drug Evaluation and Research, Food and Drug Administration, issued 8/2000, posted 8/31/2000. http //www.fda.gov/cder/guidance/ index, htm... 

Historically, the oral route of administration has been used the most for both conventional and novel drug-delivery systems. There are many obvious reasons for this, not the least of which would include acceptance by the patient and ease of administration. The types of sustained- and controlled-release systems employed for oral administration include virtually every currently known theoretical mechanism for such application. This is because there is more flexibility in dosage design, since constraints, such as sterility and potential damage at the site of administration, axe minimized. Because of this, it is convenient to discuss the different types of dosage forms by using those developed for oral administration as initial examples. 

E. Lipka and G. L. Amidon, Setting bioequivalence requirements for drug development based on preclinical data optimizing oral drug delivery systems, J. Controlled Release, 62, 41 (1999). 

Controlled Release Osmotic Drug Delivery Systems for Oral Applications... 

CDER Waiver of in vivo bioavailability and bioequivalence studies for immediate-release solid oral dosage forms based on a biopharmaceutics classification system Food and Drug Administration, 2000. 

U.S. Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research (CDER). Guidance for Industry Waiver of In Vivo Bioavailability and Bioequivalence Studies for Immediate Release Solid Oral Dosage Forms Based on a Biopharmaceutics Classification System. 2000. 

---