Promethazine and dextromethorphan and Venlafaxine interaction
Promethazine and dextromethorphan and Venlafaxine: 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 Promethazine and dextromethorphan (Promethazine Hydrochloride and Dextromethorphan Hydrobromide) label · effective 2025-08-08
…prolong, or intensify the sedative action of other central-nervous-system depressants, such as alcohol, sedatives/hypnotics (including barbiturates), narcotics, narcotic analgesics, general anesthetics, tricyclic antidepressants, and tranquilizers; therefore, such agents should be avoided or administered in reduced dosage to patients receiving promethazine.
…concomitant use of other central-nervous-system depressants such as alcohol, sedatives/hypnotics (including barbiturates), narcotics, narcotic analgesics, general anesthetics, tricyclic antidepressants, and tranquilizers; therefore such agents should either be eliminated or given in reduced dosage in the presence of promethazine (see PRECAUTIONS – Information for Patients…
From the Venlafaxine (Venlafaxine Hydrochloride) label · effective 2025-01-31
If concomitant use of Venlafaxine Extended Release Tablets with other serotonergic drugs is clinically warranted, patients should be made aware of a potential increased risk for serotonin syndrome, particularly during treatment initiation and dose increases.
If concomitant use of Venlafaxine Extended Release Tablets with other serotonergic drugs is clinically warranted, inform patients of the increased risk for serotonin syndrome and monitor for symptoms.
Serotonin Syndrome: Sertotonin syndrome has been reported with SSRIs and SNRIs, including Venlafaxine Extended Release Tablets, both when taken alone, but especially when co-administered with other serotonergic agents.
The risk is increased with concomitant use of other serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, meperidine, methadone, busipirone, amphetamines, and St.
Monoamine Oxidase Inhibitors (MAOIs) [See Dosage and Administration ( 2.6 and 2.7 ), Contraindications ( 4.1 ), and Warnings and Precautions ( 5.2 ) . ] 7.10 Other Serotonergic Drugs The concomitant use of serotonergic drugs (including other SNRIs, SSRIs, triptans, tricyclic antidepressants, opioids, lithium, buspirone, amphetamines, tryptophan, and St.
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.