Characterisation of Drug-Related Problems in HIV-Positive Patients on Antiretroviral Therapy with Comorbid Tuberculosis in Kaduna State, North West Nigeria

Background: Co-management of HIV and tuberculosis requires concurrent use of complex drug regimens, creating a high-risk environment for drug-related problems (DRPs) including interactions, adverse reactions, and adherence failures. In North West Nigeria, where HIV-TB co-infection rates are elevated, characterising DRPs in this population is a critical clinical need. This study characterised DRPs among HIV-TB co-infected patients on concurrent ART and antituberculosis therapy in Kaduna State. Methods: A prospective observational study was conducted at two HIV-TB co-infection clinics in Kaduna metropolis. Medication profiles of 180 co-infected patients were reviewed over six months. DRPs were classified using PCNE v9.1. Drug-drug interactions were identified using the University of Liverpool HIV Drug Interaction database. Results: A total of 518 DRPs were identified across 180 patients, averaging 2.9 per patient. Drug interactions between rifampicin and efavirenz were the most common (41%), followed by adverse drug reactions (hepatotoxicity 26%, peripheral neuropathy 21%). Non-adherence was identified in 34 percent of patients and was frequently associated with high pill burden. Conclusion: DRPs in HIV-TB co-infected patients in Kaduna are numerous and complex. An integrated pharmacy-led DRP management protocol is essential for this population. Keywords: drug-related problems, HIV-TB co-infection, Kaduna, antiretroviral therapy, drug interactions