Drug Interactions between bupropion / dextromethorphan and quetiapine

BuPROPion may rarely cause seizures, and combining it with other medications that can also cause seizures such as QUEtiapine may increase that risk. You may be more susceptible if you are elderly, undergoing alcohol or drug withdrawal, have a history of seizures, or have a condition affecting the central nervous system such as a brain tumor or head trauma. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

BuPROPion may increase the blood levels and effects of dextromethorphan. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Contact your doctor if you experience increased side effects or your condition changes. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

MONITOR: Coadministration of quetiapine with drugs that possess serotonergic activity (e.g., selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants (TCAs), etc.) may increase the risk of serotonin syndrome, a rare but serious and potentially fatal condition. Combining quetiapine with other serotonergic drugs may increase the risk of serotonin syndrome by relatively enhancing 5-HT1A receptor activity. However, data are currently limited to case reports. In one case report, an 85-year-old woman developed serotonin syndrome within hours of increasing quetiapine from 12.5 mg to 25 mg/day while also taking escitalopram, mirtazapine, sulpiride, and olanzapine; symptoms resolved within 48 hours after the discontinuation of all serotonergic medications. Symptoms of serotonin syndrome may include mental status changes such as irritability, altered consciousness, confusion, hallucination, and coma; autonomic dysfunction such as tachycardia, hyperthermia, diaphoresis, shivering, blood pressure lability, and mydriasis; neuromuscular abnormalities such as hyperreflexia, myoclonus, tremor, rigidity, and ataxia; and gastrointestinal symptoms such as abdominal cramping, nausea, vomiting, and diarrhea. In addition, central nervous system- and/or respiratory-depressant effects may be additively or synergistically increased in patients taking multiple drugs that also cause these effects (e.g., buspirone, desvenlafaxine, dextromethorphan, mianserin, reboxetine).

MANAGEMENT: Some authorities advise caution and closer monitoring for serotonin syndrome when quetiapine is coadministered with other serotonergic agents, especially during initiation and dose escalations. Patients should be instructed to promptly notify their healthcare provider if they experience symptoms of serotonin syndrome. If serotonin syndrome is suspected, a dose reduction or discontinuation of therapy should be considered depending on the severity of the symptoms. If serotonin syndrome develops during therapy, all serotonergic agents should be discontinued immediately, and supportive care rendered as necessary. Due to variability and occasionally prolonged half-lives of these coadministered agents, consulting individual product labeling for specific guidance is advised.