Serotonin syndrome due to fluoxetine and tramadol in renal impaired patient

Rajnish Raj, Raj Kumar, Balwant Singh Sidhu, Saurabh Yakhami


Serotonin syndrome causes confusion or altered mental status; other symptoms include myoclonus, shivering, tremors, diaphoresis, hyperreflexia, incoordination, fever and diarrhoea. Tramadol possesses dual pharmacological effects i.e., a weak opiate agonist at mu, kappa and delta opiate receptors along with reuptake inhibition of norepinephrine and serotonin. Risk associated with tramadol increases when co-administered with serotonergic antidepressants or MAOIs (monoamine oxidase inhibitors) and in renal impaired. The incidence of this syndrome is less than 1% as most of the cases remain unreported. The case highlights the fact that interaction between serotonergic agents like fluoxetine and tramadol especially in the presence of co-morbid medical illness can lead to serotonin syndrome.


Serotonin syndrome, SSRIs (Serotonin Reuptake Inhibitors), Opioids, Drug-drug interactions, CYP 450

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