Drug interactions
Flavoxate + Neostigmine
Severity: Moderate
Flavoxate and Neostigmine: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Neostigmine inhibits acetylcholinesterase and increases cholinergic activity, while flavoxate blocks muscarinic receptors. The opposing effects may reduce the efficacy of neostigmine on bladder or gut motility and its muscarinic effects.
What this interaction means in plain words
Flavoxate and Neostigmine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Flavoxate belongs to Genitourinary; Neostigmine belongs to Central Nervous System.
Why it happens
Pharmacodynamic antagonism between a cholinesterase inhibitor and an antimuscarinic agent.
What to do
Monitor the therapeutic response to neostigmine, such as bladder or bowel function. Review whether flavoxate is needed.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Flavoxate
- Clozapine + Flavoxate Major
- Abobotulinumtoxina + Flavoxate Moderate
- Aclidinium + Flavoxate Moderate
- Amantadine + Flavoxate Moderate
- Amitriptyline + Flavoxate Moderate
- Amoxapine + Flavoxate Moderate
Other interactions of Neostigmine
Frequently asked questions
Can I take Flavoxate with Neostigmine?
MediHelp rates the interaction as moderate. Flavoxate and Neostigmine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Neostigmine inhibits acetylcholinesterase and increases cholinergic activity, while flavoxate blocks muscarinic receptors. The opposing effects may reduce the efficacy of neostigmine on bladder or gut motility and its muscarinic effects.
How serious is the interaction between Flavoxate and Neostigmine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor the therapeutic response to neostigmine, such as bladder or bowel function. Review whether flavoxate is needed.
What other medicines interact with Flavoxate?
MediHelp also lists interactions of Flavoxate with, for example, Clozapine, Abobotulinumtoxina, Aclidinium. The full list is on the Flavoxate page.
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