pulsatile drug delivery

The aim of present investigation was to develop press coated tablet for pulsatile drug delivery of lornoxicam using hydrophilic and hydrophobic polymers. The drug delivery system was designed to deliver the drug at such a time when it could be most needful to patient of rheumatoid arthritis. The press coated tablets containing lornoxicam in the inner core was formulated with an outer shell by different weight ratio of hydrophobic polymer (ethyl cellulose) and hydrophilic polymers (sodium alginate). The release profile of press coated tablet exhibited a lag time followed by burst release, in which outer shell ruptured into two halves. The effect of formulation composition on the barrier layer comprising both hydrophobic and hydrophilic excipients on the lag time of drug release was investigated. It was observed that lag time decreases with increasing concentration of sodium alginate. The optimized formulation (F5) comprised 10: 90%w/w concentration ratio of sodium alginate: Ethocel 10 cps with a 245 mg coating weight, and showed a desired lag time of 308 minutes, which mimics the fluctuating symptoms of rheumatoid arthritis, followed by rapid release of lornoxicam.