Studies on the Formulation of Sustained Release Zolpidem Tartrate Matrix Tablets through Optimization and Their Evaluation

The objective of the present study was to develop a sustained release system of the hypnotic agent
zolpidem useful for the treatment of insomnia. Matrix tablet is the least complicated device to sustain
the release of drug candidates. Two polymers HPMCK4M and HPMCK15M were selected to sustain
the release up to 12 h. Optimization techniques using factorial design for two factors at three levels
(32) was selected to optimize varied response variables viz., release rate exponent (n), t50 %, k,
amount of drug released in 12 h and mean dissolution time. Software Zorel was used to calculate the
release kinetics. The design expert software was used to generate ANOVA for selected five
responses Furthermore, the in vitro and in vivo studies were performed with newly formulated
sustained- release zolpidem tablets and were compared with conventional marketed tablet (zoldem).
In vivo investigation in rabbits showed sustained- release pharmacokinetic profile of zolpidem from the
matrix tablets formulated using combination of HPMCK4M and HPMCK15M. In conclusion, the results
suggest that the developed sustained-release matrix tablets could provide quite regulated release of
zolpidem tartrate up to nearly 12 h. Conclusively, the current study attained the successful design,
development and optimization of formulation of zolpidem tartrate matrix tablets.