A survey of combination antidepressant use in Australia

Objective: The aim of this study was to survey doctors working in psychiatry in Australia about the practice of using two antidepressants simultaneously.

Method: A postal survey was sent to all doctors in psychiatry in Australia enquiring about their prescribing history and their attitudes to combination antidepressants and related issues.

Results: Seventy-nine percent of respondents had used combination antidepressants. The most frequently reported combination was a selective serotonin reuptake inhibitor combined with a tricyclic antidepressant. Combinations of mirtazepine with venlafaxine and other antidepressants were the next most frequently used. Seventeen percent of respondents reported having seen a complication from combination antidepressants, 75% believed that Australian GPs should be given information on the use of combination antidepressants, 89% wished for more information on this topic, and 88% believed patients had a right to be informed of this option in their treatment. Use of combination antidepressants was more frequent than exceeding the recommended maximum dose of an individual antidepressant.

Conclusion: Combination antidepressants are used far more frequently in Australia than suspected previously. Research into safe and evidence-based practice is strongly indicated.