Quality of Metformin Tablets in Thailand

Abstract

Background: Metformin is a drug for the treatment of patients with type 2 diabetes mellitus (T2DM). The Department of Medical Sciences reported analytical data on metformin tablets in 2006 and 2018 showing that metformin tablet samples did not meet the standard requirement of 2.33 and 0.64%, respectively. The quality of the drug is crucial for effectively controlling blood sugar levels in diabetic patient.

Objective: To examine the quality of metformin tablets from public hospitals, domestic manufacturers, and importers.

Methods: It was an experimental research during October 2021 to September 2022. We used samples of instant-acting forms of metformin tablets from government hospitals and manufacturers and importers who volunteer by surveying drugs available in public hospitals nationwide through a Google form, then selecting samples according to the Pharmacopoeia registration number and lot release number notified by the hospital and selecting the Pharmacopoeia registration number of 3-5 lot release number per lot. Then, the samples of 500 mg and 850 mg metformin tablets were collected and analyzed the quality of drugs complied with the United States Pharmacopeia (USP 2020) in identification, assay, weight variation, dissolution test, and organic impurities.

Results: A total of 46 samples were collected from 15 local manufacturers (20 registration numbers and 45 lot numbers) and 1 foreign manufacturer (one registration numbers and one lot release number). The results of identification, assay, weight variation, dissolution test, and organic impurities, all samples met the requirements.

Conclusions: All samples of metformin tablets available in public hospitals, manufacturers and an importer complied with the USP standards and has pharmaceutical equivalence. Thus, the surveillance of the quality of metformin tablets should be further continued to ensure the consumer protection.