Controlled Release Suspension: a Review

Oral drug delivery is most preferred route of drug delivery. Novel technologies with improved performance, patient compliance, and enhanced quality have emerged in the recent past. Sustained release dosage forms aimed at controlling the rate of release as well as maintaining desire drug level in the blood for long duration. An oral suspension could be the best suitable dosage form for geriatric and pediatric patients. Many therapeutic benefits could be gained by incorporating functions of sustained drug release in to suspension dosage form. They include improvement of rate and extent of drug absorption, higher patient compliance, reduction of side effects and taste masking for bitter drug. A number of techniques to obtain the sustained release oral suspension of a drug are mentioned in the article. The required drug characteristics, the stability testing and characterization of the dosage form as well as the different guidelines to follow are mentioned here. Many patent applications are already granted and many more are published in order to provide an implicit basis for the development of the sustained release suspension dosage forms of the various drugs such as Pseudoephedrine, Paracetamol, Non-steroidal anti-inflammatory drugs, Chloramphenicol, Propanalol etc.