Drug interactions
Fosphenytoin + Green tea
Severity: Minor
Fosphenytoin and Green tea: 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, an enzyme inducer that may speed the clearance of caffeine in green tea. The stimulant effect of green tea could therefore be reduced. The clinical significance is small.
What this interaction means in plain words
Fosphenytoin and Green tea 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; Green tea belongs to Gastrointestinal Tract.
Why it happens
Phenytoin induces CYP1A2 and other hepatic enzymes, increasing caffeine metabolism.
What to do
No routine action needed; patients who notice reduced stimulant effect may be informed this is expected. Caffeine intake is not expected to need adjustment.
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 Green tea
- Adenosine + Green tea Moderate
- Benzphetamine + Green tea Moderate
- Bortezomib + Green tea Moderate
- Dextroamphetamine + Green tea Moderate
- Diethylpropion + Green tea Moderate
- Ephedrine + Green tea 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 Green tea?
MediHelp rates the interaction as minor. Fosphenytoin and Green tea 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, an enzyme inducer that may speed the clearance of caffeine in green tea. The stimulant effect of green tea could therefore be reduced. The clinical significance is small.
How serious is the interaction between Fosphenytoin and Green tea?
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 action needed; patients who notice reduced stimulant effect may be informed this is expected. Caffeine intake is not expected to need adjustment.
What other medicines interact with Green tea?
MediHelp also lists interactions of Green tea with, for example, Adenosine, Benzphetamine, Bortezomib. The full list is on the Green tea page.
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