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Baraa Ramzi Abdulhameed*, Hazhar Ibrahim Karim*, Gulala Ibrahim Qader* and  Mohammed Omer Mohammed*

* Department of Pharmacology, College of Medicine, University of Sulaimani.

Submitted: 18/5/2016; Accepted: 18/10/2016/Published: 1/12/2016


Equivalence studies are needed to assess and confirm the safety and efficacy of generic formulations and are essential for the protection of patients from being treated by counterfeit medicines or from unwanted effects of medications. Two pharmaceutical products are considered to be bioequivalent when their bioavailability factors are similar and they show clinically comparable therapeutic effects.

To compare the in vitro equivalence of five products of metformin tablets available in the markets of Kurdistan Region of Iraq.

Materials and Methods
This work involved studying of five products of metformin tablets available in the markets of Kurdistan Region of Iraq. The products were compared to investigate their contents, dissolution and friability profiles.

Results of content assay indicated that all five products stayed within the standard value ranges, which should not be less than 95% and not more than 105% of labeled amount. The dissolution profile study showed that all five brands of metformin released at least 80% of their contents in 30 minutes and passed the acceptance criteria for US Pharmacopeia 2015. The friability test demonstrated that the tablets manufactured by Bristol had maximum loss while tablets manufactured by Merck showed minimum friability, as compared to other brands in the study. 

The study indicates that the five tested products of metformin tablets, which are available in Iraqi markets, Comply with the standards set by US Pharmacopeia and are considered to be equivalent to each other.


Metformin, In vitro equivalence, UV-Spectrometry.


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