We utilized a naloxone challenge strategy to investigate the functioning of the endogenous opioid system (EOS) in schizophrenia. Patients with schizophrenia, who were on neuroleptic medication or drug-free, demonstrated a significantly larger serum cortisol response to opioid blockade by naloxone than did age- and sex-matched normal controls. Patients, but not normal controls, also demonstrated an inverse relationship between baseline cortisol and the magnitude of the response. This enhanced cortisol response is consistent with tonic hyperactivity of the EOS in schizophrenia.
ASJC Scopus subject areas
- Biological Psychiatry