Burden of and factors associated with poor quality antibiotic, antimalarial, antihypertensive and antidiabetic medicines in Malawi

PLoS One. 2022 Dec 27;17(12):e0279637. doi: 10.1371/journal.pone.0279637. eCollection 2022.

Abstract

Objective: To assess the prevalence and factors associated with substandard and falsified (SF) medicines among antibiotic, antimalarial, antihypertensive and antidiabetic medicines in Malawi.

Methods: We conducted a cross-sectional study in 23 public, faith-based and private health facilities in Zomba, Machinga and Nsanje districts. We analyzed oral medicine samples of commonly used medicines among antibiotics, antimalarial, antihypertensive and antidiabetics in accordance with Malawi Essential Medicines List and local treatment guidelines. These medicines were subjected to visual inspection for any defects and screening for the content of active pharmaceutical ingredient and disintegration of dosage units. Samples that failed during screening and at least 10% of those that passed were subjected to pharmacopeia assay and dissolution test for confirmation. We used thin layer chromatography and disintegration test methods provided in the Global Pharma Health Fund minilab® for the screening purposes. We conducted confirmatory test using High-Performance Liquid Chromatography (HPLC) or ultra-violet/visible spectrophotometer and dissolution.

Results: Of the 293 medicine samples collected, 14.3% were SF medicines. Among the SF medicines were 12.5% of Amlodipine (1/8), 19.2% of Amoxicillin (5/26), 72.2% of Atenolol (8/11), 21.2% of Ciprofloxacin (7/33), 14.3% of Enalapril (1/7), 44.4% of Flucloxacillin (4/9), and 35.7% of sulfadoxine/ pyrimethamine (10/28). Medicine quality was associated with therapeutic medicine class, stated origin of manufacturer, primary packaging material and geographical location. Antimalarial and antidiabetic medicines were of better quality as compared to antibiotics, odds ratio OR 4.2 (95% CI 1.7-9.49), p < 0.002 and OR 5.6 (95% CI 1.21-26.09), p < 0.028 respectively. In terms of stated country of origin, the prevalence of SF medicines was 30% (15/50), 33% (9/27), 26.7% (4/15) and 6.6% (8/122) for medicines stated to be manufactured in Malawi, China, Kenya and India respectively.

Conclusion: This study presents the first findings on the assessment of quality of medicines since the establishment of the national pharmacovigilance center in 2019 in Malawi. It is revealed that the problem of SF medicines is not improving and hence the need for further strengthening of quality assurance systems in Malawi.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / analysis
  • Anti-Bacterial Agents / therapeutic use
  • Antihypertensive Agents / therapeutic use
  • Antimalarials* / therapeutic use
  • Counterfeit Drugs*
  • Cross-Sectional Studies
  • Folic Acid Antagonists*
  • Hypoglycemic Agents / therapeutic use
  • Malawi
  • Substandard Drugs*

Substances

  • Antimalarials
  • Antihypertensive Agents
  • Anti-Bacterial Agents
  • Counterfeit Drugs
  • Substandard Drugs
  • Folic Acid Antagonists
  • Hypoglycemic Agents

Grants and funding

This study was part of the European and Developing Countries Clinical Trials Partnership 2 (EDCTP2) programme supported by the European Union (under grant number TMA2019CDF-2768 COPSMEDS). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.