Identification and taxonomy analysis conducted at Herbarium Bogoriense at Research Centre for Biology, Indonesian Institute of Sciences Bogor. The name of the plant was C. tiglium L. The result of analysis on C. tiglium, ethanol extract as laxative material using the intestinal transit method showed treatment group that received dosage 0.06 mL/30 g b.wt. (72.5%) was significantly different compared to negative control (48.4%) or positive control (50.6%) which showed the weak effect as laxative at the dosage of 0.75 mL/30 g b.wt. It showed that ethanol extract of C. tiglium seed at dosage 0.06 mL/30 g is effective as laxative. The test result of the treatment using dosage 0.06, 0.04, 0.026 and 0.07 mL/28 g of body weight showed the mice population response 100, 60, 40 and 40% consecutively. The Thompson and Weil analysis result showed the ED50 was at 0.027 mL or equal to 639,5 g kg(-1) b.wt. The LD50 was at 0.0707 equals with 1674,5 mg kg(-1) b.wt. Safety limit is the range of dosage that cause the lethal effect and the dosage that gives the intended effect. The safety limit is represented by the comparison of LD50/ED50. Calculation result that the extract safety limit was LD50/ED50 = 0.0707/0.027 = 2.7.