Abstract: H₂ receptor antagonists are still the first line of therapy in treating gastro esophageal reflux diseases as well as other ulcers of the upper gastrointestinal tract. Accelerated stability studies of different brands of Famotidine tablets (20mg) and suspension(10mg/5ml),both liquid and dry, were carried out at 40 ^oC ± 2 ^oC (Temperature) and 75% R.H. ± 5% R.H. The assay of tablets was conducted by both HPLC and UV/Visible Spectrophotometric methods whereas for suspensions only UV/Visible Spectrophotometric method was used. The tests were conducted at 0, 1, 3 and 6 months as per guidelines of ICH for accelerated studies. The results of physical tests indicated that the dissolution of tablet decreases in all cases with time whereas disintegration of all brands was found within 15 minutes throughout the course of study while the hardness demonstrated to be decline with time. Kinetic treatment to determine rate constants and shelf lives indicated that dry suspension was more stable than liquids while the tablets showed stability for three years which was parallel to their claimed expiry. Among tablets, brand A was the most stable and among suspensions, brand C showed the longest stability. The stability studies were also carried out by using a software R-Gui (version 2.13) and results were compared with manually calculated results.

Keywords: Famotidine, Stability, Software generated shelf life,Formulations,ICH stability guidelines.