In vitro quality assessment of ten brands of metronidazole benzoate suspensions marketed in Warri, Nigeria

Therapeutic failure as a result of high incidence of fake, adulterated, counterfeit and substandard drugs usage is a major concern to health practitioners, drug regulatory agencies, drug consumers and the general public in Nigeria. The objective of this study was to carry out in vitro quality assessment/evaluation of ten (10) different brands of metronidazole benzoate suspensions that are marketed in Warri, Nigeria. Metronidazole benzoate suspensions (10 brands) were purchased from some pharmacies in Warri, Nigeria. They were checked for the label information on both the secondary and primary packages, physical examination of the primary containers for tampering/breakage of seal on cap, organoleptic properties, pH, sedimentation volume, flow rate, viscosity, redispersibility and content of active ingredient/assay using standard methods.  Results obtained showed that the suspensions had the necessary information on their labels, the containers were not tampered with in order to access or change their content. All the brands tested showed good results for color variation, pH, viscosity, flow rate, sedimentation, and redispersibility. All the brands met with their label claims of metronidazole benzoate content based on British Pharmacopoeia specification [95 - 105 %] except one brand (MET-A), that failed. Generally, nine of the brands representing 90 % met with their label claim and can be considered fit for distribution and consumption.