Pharmacoepidemiology of antiretroviral drugs in a teaching hospital in Lagos, Nigeria.

OBJECTIVE Prescribing, adherence, and adverse drug events to HAART in a large antiretroviral programme in Lagos was evaluated. DESIGN A retrospective 5 year open cohort study. SETTING The AIDS Prevention Initiative in Nigeria (APIN) clinic at LUTH is one of the United States Presidential Emergency Plan for AIDS Relief (PEP-FAR) funded centers for HIV relief program in Nigeria Participants The case files of 390 patients on HAART and attending the APIN clinic were reviewed sequel to random selection. MAIN OUTCOME MEASURES Demographics of the patients and pattern of antiretroviral (ARV) combination drugs prescribed were extracted from their case files. The details of the adverse drug events (ADEs) were extracted from drug toxicity forms regularly filled for each patient. A Chi-square test with Yates correction was used to determine the association between adherence and therapeutic outcome. RESULTS A total of 2944 prescriptions were assessed. Zidovudine + lamivudine + nevirapine (35.87%) and stavudine + lamivudine + nevirapine (35.63%) were the most frequently prescribed combinations. Over 2000 ADEs were reported with cough (13.3%), fever (8.75%) and skin rashes (8.01%) being the most frequently reported. Drug adherence was associated with good therapeutic outcome (χ(2) = 115.60, p<0.0001). CONCLUSIONS Zidovudine + lamivudine + nevirapine was the most frequently prescribed ARV combination. Cough was the most frequently reported ADE. Interventions aimed at rational prescribing of ARV drugs and improving adherence to antiretroviral drugs is essential for good therapeutic outcome in the treatment of HIV infection.