Curcuma xanthorrhiza Roxb. known as ‘Temu Lawak’ in Malaysia, is widely used in South East Asian countries in
the traditional treatment of many ailments including migraines, constipation, liver complaints and inflammatory
conditions. The present study was designed to investigate the toxicity effects of the standardized ethanolic extract of
Curcuma xanthorrhiza in experimental animals. Brine shrimp lethality test and acute oral toxicity were conducted
to evaluate the toxicity effects of this plant. The ethanolic extract of Curcuma xanthorrhiza screened for toxicity
against brine shrimps showed lethal concentration (LC50) values of more than 1.0 mg/ml confirming that the extract
was not toxic and bioactive. Oral administration of standardized ethanolic extract of Curcuma xanthorrhiza at the
doses 300, 2,000 and 5,000 mg/kg resulted in no mortalities or evidence of adverse effects, indicating that Curcuma
xanthorrhiza is non-toxic. This is further proven with the normal behavioral pattern, clinical signs of animals and
histopathology analysis of the vital organs. The experimental results suggest that the standardized Curcuma
xanthorrhiza ethanolic extract is non-toxic with a high margin of safety.