Drug interactions
Fosphenytoin + Galantamine
Severity: Minor
Fosphenytoin and Galantamine: minor 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
Fosphenytoin is converted to phenytoin, a CYP3A4 inducer that may reduce galantamine concentrations. The clinical effect is likely small but could reduce efficacy with chronic use.
What this interaction means in plain words
Fosphenytoin and Galantamine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Fosphenytoin belongs to Central Nervous System; Galantamine belongs to Central Nervous System.
Why it happens
Phenytoin-mediated CYP3A4 induction increases galantamine clearance.
What to do
No routine adjustment is needed; reassess cognitive response if therapy is long term.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Galantamine
- Galantamine + Memantine-donepezil Major
- Galantamine + Physostigmine Major
- Galantamine + Ponesimod Major
- Galantamine + Rivastigmine Major
- Amifampridine + Galantamine Moderate
- Amiodarone + Galantamine Moderate
Other interactions of Fosphenytoin
- Dronedarone + Fosphenytoin Contraindicated
- Fosphenytoin + Ledipasvir-sofosbuvir Contraindicated
- Fosphenytoin + Lorlatinib Contraindicated
- Fosphenytoin + Lurasidone Contraindicated
- Fosphenytoin + Ranolazine Contraindicated
- Fosphenytoin + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
Frequently asked questions
Can I take Fosphenytoin with Galantamine?
MediHelp rates the interaction as minor. Fosphenytoin and Galantamine have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Fosphenytoin is converted to phenytoin, a CYP3A4 inducer that may reduce galantamine concentrations. The clinical effect is likely small but could reduce efficacy with chronic use.
How serious is the interaction between Fosphenytoin and Galantamine?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No routine adjustment is needed; reassess cognitive response if therapy is long term.
What other medicines interact with Galantamine?
MediHelp also lists interactions of Galantamine with, for example, Memantine-donepezil, Physostigmine, Ponesimod. The full list is on the Galantamine page.
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