Our work focused on the impact of chronic lead acetate and manganese chloride poisoning on renal function in Wistar rats. It also tested the efficacy of the essential oil extracted from (Mentha spicata) spearmint in reversing these effects by treating previously poisoned rats with a daily intraperitoneal injection of 0.1 ml HEM/kg over a 21-days period. Analysis of this essential oil through gas chromatography coupled with mass spectrometry revealed that the main components are: carvone (42.2%), menthone (20.89%), piperitenone (17.41%) and isomenthone (7.99%). Chronic oral co-exposure to lead and manganese during periods of gestation and lactation resulted in a significant reduction (P<0.01) in both body and kidney weight. Further examination of renal function revealed significant disturbances in the quantity of markers of renal function (creatinine, urea, uric acid) in the blood. Chronic co-exposure led to the observation of disruption to antioxidant enzyme (superoxide dismutase, glutathione peroxidase and catalase) activity in poisoned rats in comparison with the control rats; these results suggest renal failure. Indeed, histological study of the kidneys revealed pronounced damage manifesting as cell degeneration with the renal parenchyma affected by inflammation. In addition, the administration of the essential oil of Mentha spicata led to the observation of an increase in body weight, regulation of the various biochemical markers, and the regeneration of damaged renal tissue, all of which proves the high importance of spearmint in traditional medicine, and its therapeutic properties in combating renal problems.