A case of iododerma, with striking facial lesions, is described. The patient was a severe asthmatic treated, inter alia, with potassium iodide. Hypersensibility to the iodine resulted in skin lesions, a marked eosinophilia, tachycardia, and proteinuria. Recovery followed the withdrawal of iodine and the administration of A.C.T.H. The mechanism of the intoxication is discussed with particular reference to the significance of the eosinophilia. A comment is made on the so-called "E.P. syndrome" and on the effect of A.C.T.H. in the recovery of the patient.