COMPARATIVE BIOEQUIVALENC E STUDIES OF SOMEBRANDS OF METRONIDAZOLE TABL ETS MARKETED IN ZARIA, NIGERIA

ABSTRACT

Multisource pharmaceutical products are intended to be pharmaceutically equivalent or pharmaceutical alternatives that are bioequivalent and hence are therapeutically equivalent and interchangeable. Thutsh,is study was aimed actarrying out a comparativien-vitro and

in-vivo bioequivalence studies of some brands of Metronidazole (200 mg) tablets marketed in Zaria, Nigeria. BP 2002 method was use for the assessment of the pharmaceutical and chemical equivalences of the samplesmoeftronidazole tablets. Tablet hardness and friability testing were also carried out to reinforce the official methods forinthveitro studies. The analytical method for thien vivo studies was adopted from the work of Kolawole and Ameh (2004).  The  methodwas  validated  according  to  ICH/WHO  guideline.  Six  healthy  human volunteers were enrolled for the studies according to the normal protocols for bioequivalence studies. The study yielded the following results: The presence of metronidazole was observed in al lthe samples with a content uniformity of 92.4-5 106.16 %. All the samples

had acceptable level of weight variation, except MT05, MT08 and MT12 with 5, 4 and 14 tablets respectively deviated from the mean weight. All the samples disintegrated within 15 minutes (BP  specification)  with  the  exception  of  MT07  which  disintegrated  in  18.97 minutes. Each of the samples had at least a dissolution of 70 % within 45 minutes. All the samples had acceptable level of friability, except MT05, MT07, MT08 and MT11 awliuthe v

of 1.70 %, 1.81 %, 1.62 % and 10.25 % respectively above the 1 % acceptable limit. All the samples of the tablets had accepetahbal rdness within thleimit of 4-10 kgF, except MT10

and MT11 with a value of 10.70 kgF and 10.6 kgF respectively. Theavteadlidmethod was found to have an intr-aand inte-rday precision of 0.491 and 0.417 % respectively expressed

as percentage relative standard deviation. The accuracy of the method was 1.98 % with a mean percentage recovery of 98.3 %. All the samples hadptacbcleelevel of bioequivaelnce

within the range of 0.9-31.05 with reference toMT01® as the reference standard using point estimate  ratio  of  the  meanmCax and  AUC0  :KQF metronidazole 200 mg tablets analysed can be used interchangeably even though there was somevariation in tehir pharmaceutical equivalences.