EPA-E, even at 3,000 mg/kg, p.o., did not affect the general behaviors, spontaneous locomotor activities, pentobarbital hypnosis and body temperature; and it did not elicit anticonvulsant, analgesic and muscle relaxant actions. It had no influence on spontaneous EEG activities, even at 3,000 mg/kg, i.d. EPA-E at concentrations up to 10(-4) M, did not affect the tonus or agonist-induced contraction of the isolated ileum, trachea, fundus and vas deferens. EPA-E had no influence on the spontaneous movement of isolated ileum or uterus. EPA-E did not affect the nictitating membrane contraction and intestinal propulsive motility, and it did not damage gastric mucosa nor elicit antiulcer action. EPA-E at 1,000 mg/kg were without effect on gastric secretory volume (SV), total acidity (TA) and pepsin activities (PA). However, EPA-E at 3,000 mg/kg significantly decreased SV and TA without significantly decreasing PA. EPA-E caused no changes in the respiration, blood pressure, heart rate and ECG at the doses up to 3,000 mg/kg; and it did not affect the heart rate and contractile force on the isolated atria at concentrations up to 10(-4) M. The intracutaneous injection of 2.0% EPA-E produced neither anesthetic nor irritative action. EPA-E did not elicit hemolytic action at 10(-4) M. EPA-E, even at 3,000 mg/kg, did not affect the neuro-muscular transmission, urine volume, urinary excretion of electrolytes and carrageenin edema. These results suggested that EPA-E has no noticeable effects on the central nervous, autonomic nervous, respiratory and cardiovascular systems and so on.