Abstract
To compare the clinical features of deliberate self-poisoning with venlafaxine and selective serotonin reuptake inhibitors (SSRIs) presenting to the emergency department of an Australian tertiary referral hospital. A retrospective cohort study comparing all 36 patients who presented with venlafaxine self-poisoning with 44 randomly selected patients with SSRI self-poisoning between 1997 and 2006. Patients who had overdosed on venlafaxine were older (mean age 37.4 versus 28.8 years, p ≤ 0.001) and generally exhibited a higher degree of suicidal intent (p ≤ 0.017). Median venlafaxine dose taken was 35 defined daily doses (DDDs) compared with SSRIs 19.4 DDDs. Those who ingested venlafaxine were more likely to become confused (25% versus 0%; p = 0) and have mydriasis (19.4% versus 2%; p ≤ 0.02), than those who took SSRIs. One patient from the venlafaxine group died. Compared with SSRI self-poisoners, patients who deliberately ingested venlafaxine were more likely to exhibit serious suicide intent. They were also more likely to be older, take a higher DDD of the drug, and have confusion and mydriasis. This has implications for management of severely depressed and suicidal patients.
Keywords: Venlafaxine, Serotonin reuptake inhibitors, Overdose, Self-poisoning, Suicide
Full Text
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Acknowledgements
Our gratitude to Dr Karen Byth and her assistant Ms Valda Wilson for their statistical input, Dr Rachel Boddy for help with accessing the toxicology database and understanding the Hunter Serotonin Toxicity criteria used, and Dr Geoff Isbister for his comments on ECG parameters and SSRIs toxicity.
Footnotes
Sources of funding: Nil in addition to hospital salary
Previous presentation: Royal Australian and New Zealand College of Psychiatrists Annual Congress, Gold Coast, Australia, May 2007
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