Quality of anthelminthic medicines available in Jimma Ethiopia

- Visual inspection including labeling results of anthelminthic medicines were in line with WHO criteria.
- Samples of ABZ, MEB and PZQ passed mass uniformity, disintegration and assay tests.
- Samples of ABZ and PZQ brands (i.e. one third of all samples) failed USP dissolution test.
- Substandard dissolution indicates a risk of reduced efficacy.

Soil-transmitted helminthiasis and schistosomiasis are major public health problems in Ethiopia. Mass deworming of at-risk population using a single dose administration of 400 mg albendazole (ABZ) or 500 mg mebendazole (MBZ) for treatment of common intestinal worms and 40 mg of praziquantel (PZQ) per kg body weight for treatment of schistosomiasis is one of the strategies recommended by World Health Organization (WHO) in order to control the morbidity of soil-transmitted helminthiasis and schistosomiasis. Since storage condition, climate, way of transportation and distribution route could all affect the quality of medicines, regular assessment by surveys is very critical to ensure the therapeutic outcome, to minimize risk of toxicity to the patient and resistance of parasites. Therefore, this study was conducted to assess the pharmaceutical quality of ABZ, MBZ and PZQ tablet brands commonly available in Jimma town (south west Ethiopia). Retail pharmacies (n = 10) operating in Jimma town were selected using simple random sampling method. Samples of anthelminthic medicines available in the selected pharmacies were collected. Sample information was recorded and encompassed trade name, active ingredient name, manufacturer's name and full address, labeled medicine strength, dosage form, number of units per container, dosage statement, batch/lot number, manufacturing and expiry dates, storage information and presence of leaflets/package insert. Moreover, a first visual inspection was performed encompassing uniformity of color, uniformity of size, breaks, cracks, splits, embedded surface spots or visual contaminations. Finally, physico-chemical quality attributes investigated encompassed mass uniformity, quantity of active pharmaceutical ingredient (API), disintegration and dissolution, all following Pharmacopoeial test methods The physical characteristics of dosage form, packaging and labeling information of all samples complied with criteria given in the WHO checklists. The mass uniformity of tablets of each brand of ABZ, MBZ and PZQ complied with the pharmacopoeial specification limits, i.e no more than 2 individual masses >5% of average tablet weight, and none deviate by more than 10%. The quantity of APIs in all investigated tablet brands were within the 90-110% label claim (l.c.) limits, ranging between 95.05 and 110.09% l.c. Disintegration times were in line with the pharmacopoeial specification limit for immediate release (IR) tablets, ranging between 0.5 and 13 min. However, the dissolution results (mean ± SD, n = 6) of one ABZ brand (i.e. Wormin®, Q = 59.21 ± 0.99% at 30 min) and two PZQ brands (i.e. Bermoxel®, Q = 63.43% ± 0.7 and Distocide®, Q = 62.43% ± 1.67, at 75 min) showed poor dissolution, failing the United States Pharmacopoeia (USP) dissolution specification limit.