Abstract
Cortisone and ACTH were used in small to massive doses for the treatment of guinea pigs which had been previously sensitized to 2,4-dinitrochlorobenzene by contact. The hormones proved ineffective in preventing or diminishing the skin reaction. Attempts to alter the course of sensitization by treatment during the sensitizing period also failed. Massive doses of the hormones (200-300 mg./kg./day) were well tolerated by the animals over a period of several days.