The effect of menthol on acute experimental colitis in rats.

Menthol is an aromatic compound with high antiinflammatory activity. The purpose of the current research is to investigate the effectiveness of menthol on acetic acid induced acute colitis in rats. Animals were injected with menthol (20 and 50 and 80mg/kg, i.p.) 24h prior to induction of colitis for 3 consecutive days. Menthol at medium and higher doses similar to dexamethasone as a reference drug significantly reduced body weight loss, macroscopic damage score, ulcer area, colon weight, colon length and improved hematocrit in rats with colitis. The histopathological examination also confirmed anti-colitic effects of menthol. Menthol also reduced significantly the colonic levels of tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), interleukin 6 (IL-6) and myeloperoxidase (MPO) activity in inflamed colons. Thus, the findings of the current study provide evidence that menthol may be beneficial in patients suffering from acute ulcerative colitis.