In vitro Comparative Quality Assessment of Different Brands of Furosemide Tablets Marketed in Northwest Ethiopia

BACKGROUND: The use of ineffective and poor quality drugs endangers therapeutic treatment and may lead to treatment failure. For desired therapeutic effect, drugs should contain the appropriate amount of active pharmaceutical ingredient and the required physical characteristics. AIM: The aim of this study was to evaluate quality as well as physicochemical bioequivalence of different brands of furosemide tablets marketed in Bahir Dar, Northwest Ethiopia. METHODS: Five different brands of furosemide tablets were purchased from community pharmacies in Bahir Dar city, Northwest Ethiopia. The quality control parameters of furosemide tablets were determined by identification, weight variation, disintegration, assay and dissolution tests and the results were compared with USP and BP pharmacopoeial standards. Difference (f1) and similarity (f2) factors were calculated to assess in vitro bioequivalence requirements. RESULTS: Identification test results revealed that all samples contained the stated active pharmaceutical ingredients. The results of weight variation tests indicated that all samples complied with USP specification limits. The active pharmaceutical ingredients quantitative assay showed that all the brands of furosemide tablets were between the 90% and 105% limit of label claim. Similarly, all samples fulfilled disintegration time (i.e., ≤30 min) and dissolution tolerance limits (i.e., Q ≥80% at 60 min). Hence, none of the samples were found to be counterfeit and/or substandard. Difference factor (f1) values were <15 and similarity factor (f2) values were >50 for all the tested brands of furosemide tablets. CONCLUSION: This study revealed that all the furosemide brands met the quality specification of weight variation, hardness, friability, dissolution, disintegration and assay. The study also indicated similarity in the dissolution profile of the brands of furosemide tablets with the innovator product. Hence, all of these generic brands could be substituted with the innovator product in clinical practice.