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Serotonin syndrome: a spectrum of toxicity

  • Rabia Ellahi
  • Please note an addendum has been issued for this article.


Serotonin syndrome (serotonin toxicity or serotonin toxidrome) is a potentially serious and theoretically predictable reaction that appears to be rarely diagnosed in practice in the UK. Some symptoms of serotonin syndrome overlap with features of other presentations in psychiatry and thus may be misattributed to mental illness (‘diagnostic overshadowing’). Further, there may be diagnostic dilemmas in patients on combinations of drugs, those receiving drugs with previously unknown serotonergic properties or where there are drug interactions. Prescriber vigilance and holistic review of the patient, including the pharmacotherapy, may be helpful in avoiding progression of serotonin syndrome to more serious outcomes.

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Corresponding author

Dr Rabia Ellahi, Ailsa Hospital, Ayr KA6 6AB, UK. Email:


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• Raised awareness of serotonin syndrome, its clinical presentation and diagnostic criteria

• Recognise multiple pathways that may contribute to the development of serotonin syndrome, with particular emphasis on the importance of the cytochrome P450 enzyme system

• Increased understanding of the importance of early management in preventing progression to more toxic states

Declaration of Interest




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Serotonin syndrome: a spectrum of toxicity

  • Rabia Ellahi
  • Please note an addendum has been issued for this article.


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Serotonin syndrome: a spectrum of toxicity

  • Rabia Ellahi
  • Please note an addendum has been issued for this article.
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