Drug interactions
Fostemsavir + Nitrofurantoin
Severity: Minor
Fostemsavir and Nitrofurantoin: 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
Fostemsavir's active moiety temsavir inhibits BCRP, and nitrofurantoin is a BCRP substrate. Exposure to nitrofurantoin may rise modestly, though clinical consequences are unlikely to be significant with short courses.
What this interaction means in plain words
Fostemsavir and Nitrofurantoin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Fostemsavir belongs to Anti Virals; Nitrofurantoin belongs to Anti Bacterial.
Why it happens
Inhibition of the BCRP efflux transporter by temsavir may increase nitrofurantoin absorption and reduce its elimination.
What to do
Usually no dose change is needed; monitor for nitrofurantoin adverse effects such as nausea, neuropathy or pulmonary symptoms during prolonged therapy.
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 Nitrofurantoin
Other interactions of Fostemsavir
- Apalutamide + Fostemsavir Contraindicated
- Carbamazepine + Fostemsavir Contraindicated
- Enzalutamide + Fostemsavir Contraindicated
- Fostemsavir + Mitotane Contraindicated
- Fostemsavir + Phenytoin Contraindicated
- Fostemsavir + Rifampicin Contraindicated
Frequently asked questions
Can I take Fostemsavir with Nitrofurantoin?
MediHelp rates the interaction as minor. Fostemsavir and Nitrofurantoin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Fostemsavir's active moiety temsavir inhibits BCRP, and nitrofurantoin is a BCRP substrate. Exposure to nitrofurantoin may rise modestly, though clinical consequences are unlikely to be significant with short courses.
How serious is the interaction between Fostemsavir and Nitrofurantoin?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Usually no dose change is needed; monitor for nitrofurantoin adverse effects such as nausea, neuropathy or pulmonary symptoms during prolonged therapy.
What other medicines interact with Nitrofurantoin?
MediHelp also lists interactions of Nitrofurantoin with, for example, Pexidartinib, Pretomanid, Aluminum hydroxide. The full list is on the Nitrofurantoin page.
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