Novel substituted steroid compounds are disclosed which are more effective than known radical-trapping agents in methods of prophylaxis and therapy of radical-mediated cell damage and of treatment of diseases due to radical-mediated cell damage. The novel substituted steroid compounds can be made from steroids having an estrane, androstane, pregnane or cholestane basic skeleton and have a radical-attracting aromatic substituent of the general formula --(CH.sub.2).sub.n X, or .dbd.CH--(CH.sub.2).sub.m X at the 17 or 6 position of the steroid nucleus, wherein X=Y, OY, SY, SeY or NHY; n=0 to 5; m=n-1 and Y is a phenyl group having five substituents A, B, C, D and E, wherein A to E is independently H, alkyl, Oalkyl, Oacyl, OH, or one of the substituents B, C or D is NR.sub.2 wherein R=alkyl and each of the other substituents is hydrogen. Pharmaceutical compositions containing the novel substituted steroid compounds and methods of making them are also part of the invention.