Desvenlafaxine and Palonosetron interaction
Desvenlafaxine and Palonosetron: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Desvenlafaxine (Pristiq Extended-Release) label · effective 2026-04-28
• Serotonin Syndrome: Increased risk when co-administered with other serotonergic agents, but also when taken alone.
If concomitant use of PRISTIQ with other serotonergic drugs is clinically warranted, inform patients of the increased risk for serotonin syndrome and monitor for symptoms.
Examples selegiline, tranylcypromine, isocarboxazid, phenelzine, linezolid, methylene blue Other Serotonergic Drugs Clinical Impact Concomitant use of PRISTIQ with other serotonergic drugs increases the risk of serotonin syndrome.
Intervention Monitor for symptoms of serotonin syndrome when PRISTIQ is used concomitantly with other drugs that may affect the serotonergic neurotransmitter systems.
The risk is increased with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, meperidine, methadone, tryptophan, buspirone, amphetamines, and St.
From the Palonosetron (posfrea) label · effective 2025-04-29
Serotonin syndrome : reported with 5-HT 3 receptor antagonists alone, but particularly with concomitant use of serotonergic drugs.
Patients should be monitored for the emergence of serotonin syndrome, especially with concomitant use of POSFREA and other serotonergic drugs.
Patients should be informed of the increased risk of serotonin syndrome, especially if POSFREA is used concomitantly with other serotonergic drugs [see Drug Interactions (7.1) ] .
Serotonergic Drugs: Monitor for serotonin syndrome; if symptoms occur, discontinue POSFREA and initiate supportive treatment ( 7.1 )
Serotonergic Drugs Serotonin syndrome (including altered mental status, autonomic instability, and neuromuscular symptoms) has been described following the concomitant use of 5-HT 3 receptor antagonists and other serotonergic drugs, including selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs).
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.