Renal Function Markers in Patients on Long-Term Use of Herbal Medicines in Imo State

The widespread use of herbal medicines in Nigeria without medical supervision has raised significant concerns about their nephrotoxic potential. This study examines renal function markers including serum creatinine, blood urea nitrogen, uric acid, and estimated glomerular filtration rate in adults who have been using herbal preparations for six months or more in Imo State, South East Nigeria. A cross-sectional comparative design was employed, recruiting 150 habitual herbal medicine users and 150 non-users matched by age, sex, and comorbidities. Venous blood and spot urine samples were collected and analysed using standard colorimetric assays. Participants were interviewed regarding the type, frequency, and duration of herbal preparation use. Blood pressure, body mass index, and history of conventional medication use were documented. The study aims to quantify the prevalence of subclinical and overt renal dysfunction associated with long-term herbal medicine use and to identify which preparation types are most strongly associated with nephrotoxicity markers. Findings will contribute to pharmacovigilance advocacy and evidence-based regulation of herbal products in Nigeria. Keywords: herbal medicine nephrotoxicity, renal function, creatinine, herbal preparations, Imo State.