Increased susceptibility to radiofrequency radiation due to pharmacological agents.

The effects of chlorpromazine, methysergide, and propranolol on thermal responses to 2.8 GHz radiofrequency radiation were examined in anesthetized rats. During intermittent exposure at an average power density of 60 mW X cm-2 (specific absorption rate, 14 W X kg-1), when colonic temperature was not allowed to rise above 39.5 degrees C, none of the pharmacological agents had any significant effects on thermal responses. When exposure was continued until lethal temperatures resulted, animals which were administered chlorpromazine, methysergide, or propranolol exhibited significantly shorter survival times than saline-treated animals. Propranolol administration caused the greatest decrease in survival time and resulted in a significantly lower lethal temperature than that which occurred in saline-treated animals.