Techniques to Improve Bioavailability of Poorly Water Soluble Drugs-A review

The mark of a successful formulation depends on how efficiently it makes the drug available at the site of action. Therapeutic effectiveness of a drug depends upon the bioavailability and ultimately upon the solubility of drug molecules especially in oral formulation. Formulating an oral dosage form for a poorly water soluble drug is in itself a challenging task. A number of ways are used to improve solubility of drug by like salt formation, cosolvency, and addition of solublizing agent, micronization, solid dispersion and complexation and many more. Although these techniques have been used to increase dissolution rate of the drug, there are practical limitations with these techniques, the desired bioavailability enhancement may not always be achieved. In this review we have tried to discuss advanced techniques that have come up to solve these problems. Here in, novel technologies, such as sonocrystallisation, nanotechnologies such as nanosuspension, nanoemulsion, spray freezing in to liquid and some commercialized technologies such as nanocrystal, nanopure, nanoedge, biorise®, diffucaps® etc. which present novel methods of solubilisation, that may allow for greater opportunities to deliver poorly soluble drugs have been dealt in detail. These techniques may help a great in facing the challenges in formulating drugs with poor water solubility.