Phenelzine and Tizanidine interaction
Phenelzine and Tizanidine: 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 Phenelzine (phenelzine sulfate) label · effective 2026-05-21
Phenelzine sulfate should not be used in combination with dextromethorphan or with CNS depressants such as alcohol and certain narcotics.
…hydrochloride desipramine hydrochloride imipramine hydrochloride doxepin carbamazepine cyclobenzaprine HCl amoxapine maprotiline HCl trimipramine maleate protriptyline HCl mirtazapine Phenelzine sulfate should be used with caution in combination with antihypertensive drugs, including thiazide diuretics and β-blockers, since exaggerated hypotensive effects may result.
From the Tizanidine (Zanaflex) label · effective 2026-01-02
The CNS depressant effects of Zanaflex with alcohol and other CNS depressants (e.g., benzodiazepines, opioids, tricyclic antidepressants) may be additive [see Drug Interactions ( 7.4 )] .
Concomitant use of Zanaflex with CNS depressants (e.g., alcohol, benzodiazepines, opioids, tricyclic antidepressants) may cause additive CNS depressant effects, including sedation.
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.