The aim of present study was to develop gastro-retentive floating tablet of Acyclovir by direct compression method. Floating tablets of Acyclovir was developed by using gas forming agents like sodium bicarbonate and natural gums like Locust bean gum, Sodium alginate and Xanthan gum by effervescent technique. Various combinations of floating polymers were used in this formulation. The floating tablets were evaluated for uniformity of weight, hardness, friability, drug content, in vitro buoyancy , buoyancy lag time and dissolution studies. The formulation optimized for different concentration of natural gums like Locust bean gum, Sodium alginate and Xanthan gum. The results of in vitro release studies showed that optimized formulation F7 could sustain drug release (99.08%) for 16 hr and remain buoyant for 24 hr. Optimized formulation F7 contained 60% of Locust bean gum and 40% Sodium alginate out of total floating polymer while amount of Xanthan gum is same in all 7 batches. F7 formulation fitted best for Korsemeyer – Peppas model and showed no significant change in physical appearance, drug content, floatability or in vitro dissolution pattern after storage at 45 °C/75% RH for two months.
