Purpose: To evaluate the diuretic activity and acute toxicity profile of the crude aqueous extract of Achyranthes aspera using animal models.

Methods: Albino rats of either sex were divided into five groups (six animals in each group). The control group received normal saline (10 ml/kg), the reference group received furosemide (10 mg/kg) and the test groups were administered different doses of the crude aqueous extract (10, 30 and 50 mg/kg) by intra-peritoneal route, respectively. At the end of 6 h, urine was collected and total volume of urine excreted by each rat was expressed as ml/6 h/100 g of body weight. pH of fresh urine samples, concentration of urinary sodium and potassium ions, Lipschitz value, diuretic index, saliuretic index and Na+/K+ ratio were also calculated to make comparison among the groups. The acute toxicity of the crude extract was assessed in Albino mice.

Results: The findings demonstrated that the crude aqueous extract of the plant showed significant diuretic (p < 0.001), natriuretic (p < 0.001) and kaliuretic (p < 0.001) effects. However, during the course of the study, urinary pH remained unchanged. The diuretic index values for the test groups (III, IV & V) were 2.3, 2.6 and 3.1, respectively. Lipschitz values showed that, at the dose of 50 mg/kg, the crude extract showed 46 % of diuretic activity as compared with furosemide. No toxic effects were observed among Albino mice even at a higher dose of 3000 mg/kg.

Conclusion: The crude extract of Achyranthes aspera increases the urine volume and concentration of urinary electrolytes in a dose-dependent manner. Therefore, this plant has a diuretic potential. However, future studies should focus on isolating the phytochemical component(s) responsible for diuresis.