In Vitro Quality Assessment of Commercially Available Azithromycin Tablets in Dhamar City, Yemen: A Comparative Study
DOI:
https://doi.org/10.59167/wpgv0y53Keywords:
Azithromycin, Quality Control, Assay, Friability, Dissolution, YemenAbstract
Background: Azithromycin is a critically important macrolide antibiotic and is listed by the World Health Organization (WHO) as an essential medicine. However, this classification does not ensure the quality of marketed products, especially in regions with weak regulatory systems. Continuous evaluation of available formulations is therefore necessary to maintain therapeutic effectiveness and protect patient safety. Objective: This study aimed to evaluate the in vitro quality of five commercially available azithromycin 500 mg tablet brands in Dhamar City, Yemen, and compare them with international pharmacopeial standards. Methods: Five brands (coded A1–A5) were tested for physical characteristics, weight variation, hardness, friability, disintegration time, assay (active ingredient content), and dissolution profile. All procedures followed the guidelines of the United States Pharmacopeia (USP), British Pharmacopoeia (BP), and Indian Pharmacopoeia (IP). Results: All brands met pharmacopeial limits for weight variation, hardness, disintegration, and dissolution (each released more than 80% of azithromycin within 30 minutes). However, Brand A5 failed the assay test, containing only 77.1% of the labelled amount (USP acceptance range: 90–110%). Brand A1 also failed the friability test, as the tablets fully disintegrated and exceeded the acceptable weight loss limit of ≤1%. Conclusion: Although four of the five brands met pharmacopeial standards, two substandard products were identified—one with a critically low active ingredient content and another with poor mechanical strength. These issues represent a serious public health concern. The results highlight the urgent need for stronger post-market surveillance and regulatory control in Yemen to prevent the distribution of ineffective or unsafe medicines.References
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Copyright (c) 2026 Neaf G. Al-Tayar, Hussein Hussein Al-Qasham, Husam Ali Al-Magrebi, Bassam Hamood Safee, Nuruddin Mohammed Al-Barati, Ali. H. AL-Osta, Najeeb N. M. Maglas, Kholood M. Al-Dhuraibi, Bushra S. Samer, Ahmed Abdulkareem Al-Sayqal (Author)
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