Psychopharmacology

, Volume 198, Issue 2, pp 243–250

Acute effects of opioids on memory functions of healthy men and women

  • James Friswell
  • Caroline Phillips
  • James Holding
  • Celia J. A. Morgan
  • Brigitta Brandner
  • H. Valerie Curran
Original Investigation

DOI: 10.1007/s00213-008-1123-x

Cite this article as:
Friswell, J., Phillips, C., Holding, J. et al. Psychopharmacology (2008) 198: 243. doi:10.1007/s00213-008-1123-x

Abstract

Introduction

Although several psychotropic drugs can acutely induce an anterograde impairment of memory which impedes new learning, they do not produce retrograde impairments, reducing memory for information learned prior to the drug being administered. However, both anterograde and retrograde memory impairments have been reported following an acute dose of morphine in palliative care patients (Kamboj et al., Pain 117:388–395, 2005).

Objective

The present study was designed to determine: (1) whether similar amnestic effects would be found after a single oral dose of either morphine or oxycodone in healthy volunteers, (2) how generalisable such effects were across a broader range of memory tasks and (3) whether men and women showed a differential response.

Materials and methods

A double-blind, placebo-controlled crossover design was used with 18 participants (nine men, nine women) who were administered 10 mg morphine, 5 mg oxycodone and placebo on three separate test days.

Results

On a working memory task, subtle impairments were found in women following both opioids whilst in men only following morphine. On an episodic memory task, women made significantly more source attribution errors after oxycodone and men made more after placebo. Most gender differences were weight related and a range of other measures showed no drug-induced impairments.

Conclusion

We conclude that these standard doses of opioids have only marginal effects on memory. If these findings can be extrapolated to patients with pain, then clinicians can feel confident in prescribing them on an outpatient basis without impacting on patients’ daily functioning.

Keywords

Morphine Oxycodone Opioid Gender Memory 

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • James Friswell
    • 1
  • Caroline Phillips
    • 1
  • James Holding
    • 2
  • Celia J. A. Morgan
    • 1
  • Brigitta Brandner
    • 2
  • H. Valerie Curran
    • 1
  1. 1.Clinical Psychopharmacology Unit, Clinical Health PsychologyUniversity College LondonLondonUK
  2. 2.UCL Centre for AnaesthesiaUniversity College London HospitalLondonUK