Purpose: To investigate the anti-urolithiatic activity of the aqueous and alcoholic extracts of Melia azedarach Linn leaves  in calcium oxalate urolithiasis in male albino rats.

Methods: The effect of oral administration of aqueous and ethanol extracts of Melia azedarach Linn leaves on calcium oxalate urolithiasis has been investigated. Lithiasis was induced by oral adminstration of ethylene glycol (0.75 %v/v) in male albino rats for 28 days. Each of the extract (250 mg/kg) was administered orally day 0 as a prophylactic regimen and from day 15 as a curative regimen. Regular administration of ethylene glycol caused hyperoxaluria in ethylene glycol-fed animals, leading to increased renal retention and excretion of oxalate, calcium and phosphate. Histopathological study, urine microscopy, serum analysis and biochemical analysis of kidney homogenate were performed.

Results: Oxalate and calcium excretion in urine increased (p < 0.01)  to 3.68 ± 0.01 and 4.5 ± 0.01 mg/24 h, respectively, in lithiatic control animals compared to (0.37 ± 0.01 and 1.27 ± 0.12 mg/24 h) for the normal control group.  Treatment with aqueous or ethanol extract (250 mg/kg, p.o.) significantly (p < 0.01) reduced the elevated levels of calcium, oxalate and phosphate excretion in urine to 0.79 ± 0.01 and 1.09 ± 0.04 mg/24 h, respectively. Following treatment with the ethanol extract (250mg/kg), serum creatinine excretion was restored from 0.95 ± 0.01 mg/24 h to the normal level of 0.87 ± 0.01 mg/24 h. The results were comparable to those of the standard drug, allopurinol (50 mg/kg p.o.). Histopathological data for the kidney supported the foregoing results.

Conclusions: The results demonstrate that the aqueous and ethanol extracts of Melia azedarach Linn leaves have potent antiurolithiatic activity against ethylene glycol-induced calcium oxalate urolithiasis in male albino rats.