[Incompatibility of olanzapine and amisulpride in multisystemic myotonic myopathy].

There is evidence for the occurrence of psychopathological symptoms in the adult form of myotonic dystrophy such as disturbance of concentration and memory, chronic depression, disturbed social behaviour, mental retardation, and hypersomnia. In this report we present a patient suffering from multisystemic myotonic myopathy without a cytosine-thymine-guanine [corrected] repeat expansion on chromosome 19q13.3 and schizophrenia. In this patient, a severe increase of creatine kinase (CK) occurred during treatment with olanzapine and amisulpride. The following risperidone medication was well tolerated without side effects. Susceptibility for malignant hyperthermia was detected by a positive in vitro contracture test. The occurrence of elevated muscle enzymes during treatment with atypical neuroleptics is suspicious as a possible side effect of neuroleptic medication and muscle disease.