This study was carried out to determine the changes in the urine levels of sodium (Na+), potassium (K+), and calcium (Ca 2+) of rats during a week of intramuscular administration of artemether (12.5 to 50.0 mg/kg/day), another one week thereafter and their concentrations in the plasma at the end of the study. At 12.5 and 25.0 mg/kg of artemether, urine Na+ concentration was significantly increased throughout the study (p< 0.05), except on Day 7 (at 12.5 mg/kg) and Day 11 (at 25.0 mg/kg), when it was not significantly different from the control. At 12.5 mg/kg of the drug, urine K+ concentration was significantly increased throughout the study (p< 0.05). Artemether caused no significant changes in urine Ca 2+ concentration in the control rats as well as those that received 12.5 and 25.0 mg/kg of artemether. Progressive and significant reductions in the urine concentrations of all the electrolytes at 50.0 mg/kg of artemether were observed. Their concentrations in the plasma were also significantly reduced at this dose of the drug. A dose-dependent degeneration of the renal tissue of all the experimental rats was also observed. We concluded that high doses of artemether caused progressive degeneration of the renal tissue of rats, inability of the damaged kidneys to concentrate urine, which manifested as excessive water loss and electrolyte depletion