Synonyms: 5a-Pregnan-20-one, 3b,17,21-trihydroxy- (8CI);Pregnan-20-one, 3b,17,21-trihydroxy-(7CI); 3b,17,21-Trihydroxy-5a-pregnan-20-one; 3b,17a,21-Trihydroxy-5a-pregnan-20-one; Allopregnane-3b,17a,21-triol-20-one; Compound P; Reichstein's substance P