Delirium associated with concomitant use of duloxetine and bupropion in an elderly patient

Abstract

Delirium is common in daily practice. Drug-induced delirium constitutes approximately one-third of all cases of delirium. In cases characterized by the limited efficacy of a single antidepressant, a combination of two antidepressants is required, which may induce a complex drug-drug interaction. We reviewed a case of duloxetine- and bupropion-related delirium in an elderly male patient in our clinical practice. The patient was diagnosed with major depressive disorder and was treated with duloxetine. However, he developed delirium 10 days after bupropion was added to his treatment regimen. Three days after the cessation of bupropion, his delirious condition gradually improved. Duloxetine and bupropion are both cytochrome P450 2D6 inhibitors that may result in a higher level of hydroxybupropion. An increased level of hydroxybupropion may cause the elevation of dopamine and a risk of subsequent delirium. We should be aware of the risk of delirium induced by drug-drug interactions.

Delirium in psychiatric settings: risk factors and assessment tools in patients with psychiatric illness: a scoping review

“…The type of pharmacological treatment associated with delirium include non-psychotropic medication (anticholinergic drug and antibiotics) and psychotropic medication [ 45 ]. Psychotropic medication associated with delirium were antipsychotics [ 5 , 17 , 37 , 38 , 46 ], antidepressants [ 17 , 47 , 48 ], mood stabilizer [ 37 ], and no use of benzodiazepines [ 39 ]. Specifically, antipsychotics strongly associated with delirium, was olanzapine [ 48 ].…”

“…Specifically, antipsychotics strongly associated with delirium, was olanzapine [ 48 ]. Antidepressants associated with delirium include, duloxetine and bupropion [ 47 ], and tricyclic antidepressant drugs [ 48 ]. Mood stabilizer associated with delirium was lithium [ 37 ].…”

Serotonin Syndrome Precipitated by Amantadine in a Patient With Persistent Post Concussive Symptoms – A Case Report

“… 20 Given that the patient had been on the same dose of duloxetine since injury with the same dose of bupropion for over 6 weeks prior to the onset of any symptoms related to SS, this interaction is unlikely to have been a primary direct cause of SS. The case reports of bupropion-associated SS are primarily related to bupropion overdose or a combination of bupropion with other serotonergic agents, 21 , 22 , 23 , 24 , 25 and cases of SS involving bupropion have predominantly been reported acutely after a medication change/adjustment, 22 with only 1 study demonstrating SS occurring after 3 weeks. 23 The possibility that the duloxetine/bupropion combination solely contributed to SS in this patient cannot be completely ruled out; however, given a case series of 14 individuals who developed SS at a mean of 6 weeks post medication changes, though none of which involved bupropion or duloxetine.…”