EVALUATION OF THE PHYSICOCHEMICAL PROPERTIES AND QUALITY INDICES OF MULTISOURCED 5 MG AMLODIPINE BESYLATE MARKETED IN SOUTHERN NIGERIA
Objectives: This study was carried to evaluate and compare the physicochemical parameters and cost of available brands of amlodipine besylate 5 mg marketed in Southern Nigeria.
Methods: Fifteen brands were subjected to weight uniformity, friability, hardness, disintegration time, dissolution and chemical content tests. The chemical content test was performed using RP-HPLC method with isocratic run using acetonitrile: acetone buffer (50:50) as mobile phase at a flow rate of 0.8 ml/min and 237 nm wavelength of detection.
Results: All the brands tested passed the weight uniformity test with no significant difference in values within each brand at p<0.05. The crushing strength values of only five brands were within official specification. All the brands passed the disintegration time and friability tests while only ten brands passed the content assay. The dissolution test revealed that all the brands released 70 % of their drug content within 45 min. The shelf price of the innovator product was N8, 500 (USD 43) for a pack of 100 tablets while the other products were about N3,000 (USD 15) for an equivalent pack.
Conclusion: It can be concluded that though all the brands tested showed good dissolution profiles, only ten brands could be regarded as pharmaceutical equivalents according to their content assay and the price disparity between the products studied cannot be justified by the outcome of this physicochemical evaluation.
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