Phenobarbital and Phenobarbital, hyoscyamine, atropine, and scopolamine interaction
Phenobarbital and Phenobarbital, hyoscyamine, atropine, and scopolamine: the Phenobarbital prescribing label flags 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 Phenobarbital (SEZABY) label · effective 2025-12-23
SEZABY is contraindicated in patients with: acute porphyrias [see Warnings and Precautions (5.8)], or a history of hypersensitivity reaction to phenobarbital or other barbiturates [see Warnings and Precautions (5.7)] Acute porphyrias (4)
Hypersensitivity to phenobarbital or other barbiturates (4)
SEZABY is contraindicated in patients who have experienced hypersensitivity to phenobarbital or other barbiturates.
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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.