The acute and subacute toxicities and pharmacological actions of two preparations of Ssanghwa Tang prescriptions have been evaluated in mice, rats and rabbits. The two prescriptions were found to be safe drugs because those preparations exhibited almost no acute and subacute toxicities even at a high dosage level. The two prescriptions elicited CNS depressant activities characterized by potentiation of hexobarbital-induced narcosis, antipyretic activity in typhoid-vaccinated rabbits and a significant antifatigue effect against cold immobilized stress, the activities of prescription B being more potent.