Raised plasma metenkephalin in patients who habitually mutilate themselves.

Mean plasma metenkephalin concentration was significantly higher in ten patients who habitually mutilated themselves than in matched, healthy controls. No differences were found in corticotropin, N-lipotropin or C-lipotropin (beta-endorphin). Plasma metenkephalin was raised only in the five patients receiving hospital treatment because of their behaviour disorder. It was not raised in those patients sufficiently well to have been discharged from hospital.