Drug interactions
Fosaprepitant + Theophylline
Severity: Minor
Fosaprepitant and Theophylline: 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
Fosaprepitant is converted to aprepitant, a moderate CYP3A4 inhibitor, but as a single dose the effect is short lived. Theophylline is mainly metabolized by CYP1A2, so any increase is minor.
What this interaction means in plain words
Fosaprepitant and Theophylline have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Fosaprepitant belongs to Gastrointestinal Tract; Theophylline belongs to Respiratory.
Why it happens
Transient CYP3A4 inhibition by aprepitant affects a minor theophylline pathway.
What to do
No routine adjustment is needed; monitor for theophylline toxicity if the patient is at high risk.
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 Theophylline
- Riociguat + Theophylline Contraindicated
- Adenosine + Theophylline Major
- Apalutamide + Theophylline Major
- Bupropion + Theophylline Major
- Carvedilol + Theophylline Major
- Cimetidine + Theophylline Major
Other interactions of Fosaprepitant
- Flibanserin + Fosaprepitant Contraindicated
- Fosaprepitant + Pimozide Contraindicated
- Alprazolam + Fosaprepitant Moderate
- Amiodarone + Fosaprepitant Moderate
- Amobarbital + Fosaprepitant Moderate
- Apalutamide + Fosaprepitant Moderate
Frequently asked questions
Can I take Fosaprepitant with Theophylline?
MediHelp rates the interaction as minor. Fosaprepitant and Theophylline have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Fosaprepitant is converted to aprepitant, a moderate CYP3A4 inhibitor, but as a single dose the effect is short lived. Theophylline is mainly metabolized by CYP1A2, so any increase is minor.
How serious is the interaction between Fosaprepitant and Theophylline?
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; monitor for theophylline toxicity if the patient is at high risk.
What other medicines interact with Theophylline?
MediHelp also lists interactions of Theophylline with, for example, Riociguat, Adenosine, Apalutamide. The full list is on the Theophylline page.
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