Evaluating drug interactions, adverse drug reactions, and level of adherence to highly active antiretroviral therapy regimen amongst HIV-positive patients who referred to an AIDS healthcare center in Fars, southern Iran: the first multifaceted study from Iran

Introduction: To the best of our knowledge, this is the first multifaceted study from Iran that has evaluated the adverse drug reactions (ADR), drug-drug interactions (DDIs), and patient adherence to highly active antiretroviral therapy (HAART) regimen collectively. The HAART regimen is the most effective regimen in the treatment human immunodeficiency virus (HIV). However, this regimen is associated with ADRs and lack of adherence as well as DDIs.

Material and methods: This prospective cohort study was done from October 2014 to March 2015 on 200 HIV-positive patients who referred to an HIV/AIDS Research Centre receiving HAART regimen. DDIs was checked by lexi-com® software and Naranjo scale was used to evaluate the reported ADRs and then adherence of patients was evaluated by self-report.

Results: 96.50% of the patients reported at least one ADR. The central nervous system (n = 575, 28.87%), gastrointestinal (n = 567, 28.47%), and musculoskeletal adverse effects (n = 237, 11.90%) were the most commonly reported. Overall, 302 DDIs, category C, D, and X, were recorded, of which, 259 interactions (85.8%) were type C, 42 interactions (13.9%) were type D, and only one interaction (0.3%) was type X. 80 patients (40%) had a history of discontinuation and did not use at least one dose of their medications. The main reasons for non-adherence to the regimen included: forgetfulness (43.75%), unavailability of antiretroviral medications (23.75%), and ADR (7.55%).

Conclusions: This study showed a significant number of ADRs, DDIs, and nonadherence exist in our patients . It is clear that interventions for enhancing the ability of HIV-infected patients to cope with HAART regimens are warranted.