To evaluate seasonal influences on the dexamethasone suppression test (DST), cortisol and melatonin responses to dexamethasone were assessed in drug-treated chronic schizophrenics and in drug-free healthy volunteers in different seasons of the year, according to a longitudinal study design. In schizophrenic patients, there was a greater rate of cortisol non-suppression to DST in February as compared to November and May (χ2 = 4.5, p = 0.03) with no significant differences in pre- and post-dexamethasone plasma cortisol levels. In healthy volunteers, in contrast, no seasonal variation in DST results was observed. Moreover, dexamethasone administration did not significantly affect morning plasma melatonin levels in either patients or healthy controls. These findings suggest that seasonality may be of critical importance in evaluating DST results in schizophrenic patients, but not in healthy subjects.

This content is only available via PDF.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.