Lithium prophylaxis of corticotropin-induced psychosis.

Corticotropin is one of the few accepted treatments for acute exacerbations of multiple sclerosis and retrobulbar neuritis. Psychosis is a serious side effect usually necessitating discontinuation of the drug therapy. Because mood disorders preponderated in most patients previously described with this psychosis, 27 patients were empirically treated with lithium carbonate concurrently with corticotropin. In none of the patients treated with lithium did a psychotic reaction occur, although in a comparable group of 44 patients previously treated identically with corticotropin but without lithium, six (14%) became psychotic.