Tapentadol: seizure and serotonin syndrome risk when taken with other medicines

11 Jan 2019

The MHRA drug safety update on tapentadol, which may increase seizure risk and cause serotonin syndrome when co-administered with other medicines

The Medicines & Healthcare products Regulatory Agency (MHRA) has published a drug safety update highlighting:

  • The potential risks of seizures when tapentadol (PALEXIA®) is co-administered with medicines which lower seizure threshold, for example, antidepressants (including selective serotonin norepinephrine reuptake inhibitors (SNRIs), serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs)) and antipsychotics
    • Tapentadol (PALEXIA®), like all opioid medicines can induce seizures, therefore, it should be prescribed cautiously in patients with a history of epilepsy or seizure disorders
  • Reports of serotonin syndrome when tapentadol is co-administered with serotoninergic antidepressants (including SNRIs, SSRIs and TCAs) and antipsychotics
    • Serotonin syndrome include, hypertonia, inducible/ocular clonus with agitation or sweating, increase of body temperature above 38C, and tremor
    • Withdrawing serotoninergic medicines with supportive symptomatic care usually allows a quick improvement in serotonin syndrome – abrupt cessation can induce withdrawal symptoms


The Summary of Product Characteristics (SPCs) and Patient Information Leaflets (PILs) for tapentadol now include strengthened warnings on seizure risk and the above interactions

  • Advice has also been included to avoid monoamine oxidase inhibitors (MOIs) as there is a potential for hypertensive crisis to occur


Reporting drug interactions

The MHRA are reminding healthcare professionals to report all suspected adverse drug interactions (ADRs) to the Yellow Card Scheme – this is via the Yellow Card website or Yellow Card App available on iOS devices and Android devices


NPA advice for pharmacists

  • Ensure any interactions flagged with tapentadol are queried with the patient’s prescriber
  • Highlight serotonin syndrome symptoms to patients so they know what to look out for and what steps to take
  • Make necessary notes on the patient’s medication record
  • Report suspected ADRs to the Yellow Card Scheme


For further information on this or any other query, please contact the NPA Pharmacy Services team on 01727 891 800 or email pharmacyservices@npa.co.uk.

Produced by the NPA Pharmacy Services team January 2019.