The aim of the study was to evaluate the effect of different lubricants on pharmaceutical effectiveness of metronidazole tablets determined by the rate of release of drug from the dosage form. Different lubricants, like magnesium stearate, talc and the combination of both were used to prepare metronidazole tablets by direct compression method. The tablets were tested for quality control parameters such as uniformity of weight, thickness, diameter, contents assay, hardness, friability and disintegration time. Formulations were tested for the releasing pattern of drug from tablets by in-vitro dissolution test. Better results were achieved from formulation having magnesium stearate as lubricant based on compression force value. The content uniformity for all the three formulations was found in the range of 96.71 to 99.61%, while hardness was in the range of 7.39±0.341 to 10.375±0.95 Kg. The formulated tablets were also analyzed for dissolution profile which was more than 85% within 20 minutes. Then it was compared with dissolution profile of marketed products for quality and similarity analysis. Lubricant plays a key role in successful manufacturing of pharmaceutical solid dosage forms. Many failures in pharmaceutical manufacturing operations, directly or indirectly, can be controlled by appropriate screening of lubricants.

No 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 o C ± 2 o C (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.