Ferulago carduchorum Boiss. & Hausskn. (Apiaceae) is known as Chavil in Persian which grows in west of Iran. Local people add Chavil to dairy and oil ghee as a natural preservative to extend the expiration date. The goal of this survey is the safety evaluation of the total extract of F. carduchorum in rats by determining both oral acute and subchronic toxicities; furthermore, the anticoagulant activity of isolated coumarins was evaluated. The aerial parts of F. carduchorum were extracted by the percolation method. The anticoagulant activity of isolated coumarins was evaluated and the total extract was used to investigate acute and subchronic toxicity in rats. In the subchronic toxicity model, doses of 250, 500, and 1000 mg/kg of the extract were administered to treated groups for 30 consecutive days by gavage. According to the results of acute toxicity, the LD50 of Chavil extract was more than 2000 mg/kg. The subchronic study showed no significant difference (p > 0.05) between the groups treated with extract and control groups in hematological (erythrocyte, total and differential leukocyte, hematocrit, hemoglobin, platelet count) and biochemical parameter (glucose, albumin, cholesterol, triglycerides, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase) evaluations. The isolated coumarins (suberosin and suberenol) prolonged the prothrombin time (PT) at doses of 3 and 6 mg/kg compared with control (p < 0.05). The longest PT was for suberosin at 6 mg/kg (17.4 s). In conclusion, oral administration of the Chavil extract did not cause either acute or subchronic toxicities although the coumarins showed anticoagulant effect in rats.