Monoamine oxidase inhibitors: potential for drug abuse.

Both the amphetamines and MAO inhibitors share common clinical and pharmacological properties, namely, (i) to clinically induce euphoriant-stimulating type and psychotomimetic effects in certain individuals, and (ii) to increase, albeit by different mechanisms, the amount of functionally available neurotransmitter (catecholamines and indoleamines) at the receptor site. The present data now indicate that, like the amphetamines, the use of MAO inhibitors can be clinically associated with dependence-tolerance. Perhaps these clinical findings will converge with other clinical-biochemical data in helping to define the specific amine(s) responsible for not only the clinical effects of these drugs but also the etiopathogenesis of major psychiatric illnesses such as the affective disorders and schizophrenia.

beta-Endorphin and naloxone in psychiatric patients: clinical and biological effects.

The authors conducted single- and double-blind studies of the responses of 7 chronic male schizophrenic patients to 10 mg of naloxone. BPRS ratings were made before and 6 hours after the injection; ACTH blood levels were determined before and 1 1/2 and 6 hours after injection. Statistically significant improvement of psychotic behavior occurred after 6 hours. The greatest improvement occurred in the patient who showed the most pronounced diurnal variation of ACTH levels, and there was no improvement in the patient who had no diurnal changes. Prolactin plasma levels following endorphin injections were apparently dose-dependent and peaked at approximately 30 minutes. The mean half-life of elimination of exogenous beta-endorphin was between 12 and 35 minutes. The authors theorize that positive and negative behavioral responses to naloxone depend--as possibly do many placebo responses in general--on the relative stress produced by experimental or therapeutic interventions.

A controlled comparison of trimipramine and amitriptyline.

Depressed patients seen in a private psychiatric practice (N = 41) were randomly assigned to receive trimipramine or amitriptyline over a study period of at least 4 weeks. Patients in both groups showed significant improvement over time on measures of mood and depression, and on psychological scales. Only one variable, the global improvement rating, showed a significant overall between-groups difference, which favored amitriptyline treatment. This difference may reflect the presence of significantly less baseline symptomatology in the amitriptyline group. Trimipramine patients were more seriously ill on initial diagnosis and showed significantly more improvement at week 2 than amitriptyline patients and a trend toward fewer side effects. Thus, trimipramine may be useful for patients particularly sensitive to side effects in whom evidence of early response is important.