Drug interactions
Fexofenadine + Letermovir
Severity: Minor
Fexofenadine and Letermovir: 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
Letermovir inhibits OATP1B1/1B3 and may raise fexofenadine concentrations. Fexofenadine has a wide therapeutic index, so the increase is usually tolerable.
What this interaction means in plain words
Fexofenadine and Letermovir have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Fexofenadine belongs to Respiratory; Letermovir belongs to Anti Virals.
Why it happens
Inhibition of OATP1B1/1B3-mediated hepatic uptake of fexofenadine increases systemic exposure.
What to do
No empiric adjustment is needed; monitor for antihistamine adverse effects and reduce the dose if they occur.
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 Fexofenadine
- Danicopan + Fexofenadine Moderate
- Erdafitinib + Fexofenadine Moderate
- Fexofenadine + Glecaprevir / pibrentasvir Moderate
- Fexofenadine + Grapefruit Moderate
- Fexofenadine + Juice Moderate
- Acrivastine + Fexofenadine Minor
Other interactions of Letermovir
- Ergotamine + Letermovir Contraindicated
- Letermovir + Pimozide Contraindicated
- Apalutamide + Letermovir Major
- Atorvastatin + Letermovir Major
- Carbamazepine + Letermovir Major
- Colchicine + Letermovir Major
Frequently asked questions
Can I take Fexofenadine with Letermovir?
MediHelp rates the interaction as minor. Fexofenadine and Letermovir have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Letermovir inhibits OATP1B1/1B3 and may raise fexofenadine concentrations. Fexofenadine has a wide therapeutic index, so the increase is usually tolerable.
How serious is the interaction between Fexofenadine and Letermovir?
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 empiric adjustment is needed; monitor for antihistamine adverse effects and reduce the dose if they occur.
What other medicines interact with Fexofenadine?
MediHelp also lists interactions of Fexofenadine with, for example, Danicopan, Erdafitinib, Glecaprevir / pibrentasvir. The full list is on the Fexofenadine page.
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