The psychotropic medications reviewed in this paper have widespread clinical applicability in psychiatry and other branches of medicine. These drugs clearly can alter peripheral regulation of hypothalamic-pituitary-adrenal axis hormones. In general, psychotropic medications when administered acutely have a tendency to increase the output of both adrenal and pituitary hormones associated with the axis; the benzodiazepines appear to be the exception and indeed may decrease axis activity. Psychotropic agents may also alter the results of the dexamethasone suppression test as currently used in psychiatry, since they alter the neurotransmitters that regulate corticotropin-releasing hormone secretion and also because they may change the severity of the underlying pathophysiology. Withdrawal of these drugs after long-term administration may cause an elevation of these hormones, potentially increasing the false-positive rate of the dexamethasone suppression test and other neuroendocrine tests.