Multiple muscle enzyme release with psychiatric illness. Associations (p less than .001) between serum concentrations of lactate dehydrogenase (LDH) and glutamic oxaloacetic transaminase (SGOT) were observed in physically well patients with mania (N = 100, r = .70), depression (N = 138, r = .51), chronic schizophrenia (N = 85, r = .68), and schizoaffective or atypical psychosis (N = 39, r = .52) discharged from 1978 through 1981. In contrast, there was a negligible association between these enzymes in 90 nonpsychiatric inpatient control subjects. Patients with mania (229.0 +/- 106.1 IU/l) showed significantly (t = 3.16, p less than .002, two-tailed) higher lactate dehydrogenase (LDH) levels than control subjects (191 +/- 41.7 IU/l) and a 14% incidence of abnormally high serum LDH levels vs. 1% among control subjects. Results were unchanged when patients taking neuroleptics were excluded. These results indicate that psychiatric illness, especially mania, induces release of LDH and SGOT, occasionally to unusually high levels. This is similar to previous reports of muscle creatine phosphokinase release in psychiatric patients. Presumably, these enzymes are released from skeletal muscle in association with agitation, with muscle tension, or with blood stasis and local tissue hypoxia consequent to hypoactivity. 