Influence of D-or DL-propranolol and chlorpromazine on habituation of phasic electrodermal responses in schizophrenia.

Propranolol was found to share the properties of the racemate in facilitating habituation of the electrodermal orienting reflex in schizophrenic patients. This effect appeared independent of influences on levels of skin conductance and non-specific responses. Chlorpromazine did not normalise orienting activity. If the findings from open clinical studies that D-propranolol has anti-psychotic properties are confirmed, the fact that dextro propranolol has only minimal cardiovascular effects may give it important advantages as an anti-psychotic agent. Controlled clinical studies to prove its therapeutic action and neurobiological studies to determine its central mechanisms of action are warranted.