Acute Radiation Exposure

Laird and Fonner, U.S. Army Medical Research Lab, Fort Knox, Ky. (1957),213 studied the protective effects of PHT in the hyperacute radiation syndrome. Pretreatment with PHT (94 mg/kg) delayed the onset and reduced the severity of convulsive activity and increased the median survival time as much as three-to ten-fold in mice exposed to massive doses of x-radiation (between 55,000 and 150,000 roentgens), compared with controls.

213. Laird, R. D. and Fonner, R. L., The protective effect of sodium diphenylhydantoin in the hyperacute radiation syndrome, U.S. Army Med. Res. Lab., Fort Knox, Kentucky, Report No. 262, 1957.

LeVan, Gordon and Stefani, Journal Of Pharmaceutical Sciences (1970),1267 compared survival of mice exposed to 750 rads whole-body irradiation, with and without PHT pretreatment. There were 450 animals in each group. PHT (3 mg/kg, intraperitoneally) significantly prolonged survival of the irradiated mice. By the nineteenth day after irradiation, all of the control animals had died. At thirty days, 55% of the PHT-treated animals were still alive.

1267. LeVan, H., Gordon, P., and Stefani, S., Enhancement of radioresistance in mice treated with diphenylhydantoin, J. Pharm. Sci., 59: 1178-1179, 1970.

Curran and El-Mofty, Journal of Dental Research (1983),2420 reported that PHT (20-50 mg/kg) protected normal rat parotid gland from the damaging effects of a single x-ray dose of 2000 rads, in a dose-dependent manner. Damage was assessed histologically and by serum amylase. The authors attribute this protective effect to PHT's calcium-antagonist actions.

2420. Curran, A. E., El-Mofty, S. K., Protection of irradiated parotid by phenytoin (DPH), J. Dent. Res., 62: 232, 1983.