Physostigmine and Pyridostigmine interaction
Physostigmine and Pyridostigmine: 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 Pyridostigmine (Pyridostigmine bromide) label · effective 2026-05-13
Pyridostigmine bromide extended-release tablets are contraindicated in patients with: Mechanical intestinal or urinary obstruction Known hypersensitivity to pyridostigmine or other anticholinesterase agents Mechanical intestinal or urinary obstruction.
Known hypersensitivity to pyridostigmine or other anticholinesterase agents.
Other Anticholinesterase Drugs Concomitant use of anticholinesterase drugs used in the treatment of glaucoma and pyridostigmine bromide may have an additive effect that may cause or exacerbate problems with night vision.
From the Physostigmine (ANTICHOLIUM) label · effective 2025-11-11
In case of simultaneous administration of other cholinesterase inhibitors (e.g. medicines for the treatment of dementia), caution should be exercised because of the potentiating effect.
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.