SEROTONIN SYNDROME AFTER CHALLENGE WITH THE 5-HT AGONIST META-CHLOROPHENYLPIPERAZINE

meta-Chlorophenylpiperazine (mCPP) is a non-selective 5-HT-receptor ag onist/antagonist that is used extensively in psychiatry to assess cent ral serotonergic function. We report on three patients who developed s ymptoms of the serotonin syndrome when they participated in an mCPP (0 .5 mg/kg body weight p.o.) challenge test as part of a research protoc ol. They had relatively high plasma mCPP concentrations. The syndrome did not occur in normal volunteers who had comparable plasma concentra tions of mCPP. Investigators should be aware of the possible occurrenc e of the serotonin syndrome after a single oral dose of mCPP. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.