BackgroundAspartame is used to treat obesity, and the diabetic people could induce changes in liver and kidney structures and function. Garlic extract, melatonin and thymoquinone have an important role against aspartame toxicity due to their antioxidant properties. The current study was designed to examine the protective effects of garlic, melatonin and thymoquinone against aspartame-induced hepatorenal toxicity in albino rates.ResultsThe results indicated that aspartame induced changes in the serum levels of liver parameters function (glucose, ALT, AST and ALP) and renal parameters function (urea and creatinine). Garlic, melatonin and thymoquinone reversed the values of liver and kidney enzymes levels near to or similar to that of control. The histopathological effects of aspartame on the histological structures of liver and kidney were either reduced or removed by garlic, melatonin and thymoquinone.ConclusionLong-term (6 months) administration of aspartame induced toxic effects on hepatorenal function and structure, whereas garlic, melatonin and thymoquinone resulted in hepatorenal ameliorative and protective effects.