Diphenhydramine and Sevoflurane interaction
Diphenhydramine and Sevoflurane: 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 Diphenhydramine label · effective 2026-03-05
Use as a Local Anesthetic Because of the risk of local necrosis, this drug should not be used as a local anesthetic.
Drug Interactions Diphenhydramine hydrochloride has additive effects with alcohol and other CNS depressants (hypnotics, sedatives, tranquilizers, etc).
From the Sevoflurane (Ultane) label · effective 2025-01-13
Consider having an anticholinergic and epinephrine available when administering sevoflurane for induction in this patient population.
In most cases, bradycardia improved with decreasing the concentration of sevoflurane, manipulating the airway, or administering an anticholinergic or epinephrine.
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.