Six weeks of diazepam treatment in normal women: effects on psychomotor performance and psychophysiology.
Effects of a therapeutic dose of diazepam (15 mg daily), administered over a 6-week period, were assessed in nonanxious female volunteers. No acute effects of the 5-mg dose of diazepam on performance were observed, but two types of effects were observed on physiology: (1) direct changes on some measures (e.g., skin conductance) and (2) an absence or attenuation of changes expected on the basis of data obtained with a placebo group. The latter effect was found for systolic blood pressure both initially and again after 6 weeks of medication. When performance measured in the morning prior to the first 5-mg dose was compared with that of the morning prior to the last 5-mg dose, 6 weeks later, two types of impairment were found in the diazepam group: (1) decrements in performance (e.g., digit span) and (2) a failure to show expected improvement (e.g., DSST). Performance impairment due to reduced motivation was ruled out by a motivational component of the test battery. Performance tended to return to predrug levels 2 weeks after discontinuation of medication. When physiology was measured in the morning prior to the first dose of the day, 6 weeks of treatment produced decreases in skin conductance, diastolic blood pressure, and heart rate. Blood pressure and heart rate, but not skin conductance, returned to predrug levels 2 weeks after discontinuation of medication. Results of this study indicate that the long-term effects of diazepam can differ from the acute effects and that both acute and long-term effects can take at least two forms, depending upon the behavior or physiological process measured.
McLeod
D R
DR
Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Hoehn-Saric
R
R
Labib
A S
AS
Greenblatt
D J
DJ
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D003975:Diazepam / Q000009:adverse effects / Q000097:blood / Q000494:pharmacology*; D004334:Drug Administration Schedule; D004576:Electromyography; D005260:Female; D005712:Galvanic Skin Response / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D009042:Motivation / Q000187:drug effects; D009132:Muscles / Q000187:drug effects / Q000502:physiology; D011597:Psychomotor Performance / Q000187:drug effects*; D011603:Psychophysiology; D012650:Self Disclosure
D003975:Diazepam