Drug interactions
Clarithromycin + Larotrectinib
Severity: Major
Clarithromycin and Larotrectinib: major 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
Larotrectinib is a CYP3A4 substrate, so clarithromycin can raise its concentrations. This may increase adverse effects such as hepatotoxicity, dizziness and neurotoxicity.
What this interaction means in plain words
Clarithromycin and Larotrectinib can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Clarithromycin belongs to Anti Bacterial; Larotrectinib belongs to Oncology.
Why it happens
Strong CYP3A4 inhibition decreases larotrectinib clearance.
What to do
Avoid the combination if possible. If unavoidable, reduce the larotrectinib dose by about half per labeling and monitor for toxicity and liver enzymes.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Clarithromycin
- Astemizole + Clarithromycin Contraindicated
- Avanafil + Clarithromycin Contraindicated
- Cisapride + Clarithromycin Contraindicated
- Clarithromycin + Colchicine Contraindicated
- Clarithromycin + Conivaptan Contraindicated
- Clarithromycin + Dihydroergotamine Contraindicated
Other interactions of Larotrectinib
Frequently asked questions
Can I take Clarithromycin with Larotrectinib?
MediHelp rates the interaction as major. Clarithromycin and Larotrectinib can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Larotrectinib is a CYP3A4 substrate, so clarithromycin can raise its concentrations. This may increase adverse effects such as hepatotoxicity, dizziness and neurotoxicity.
How serious is the interaction between Clarithromycin and Larotrectinib?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination if possible. If unavoidable, reduce the larotrectinib dose by about half per labeling and monitor for toxicity and liver enzymes.
What other medicines interact with Clarithromycin?
MediHelp also lists interactions of Clarithromycin with, for example, Astemizole, Avanafil, Cisapride. The full list is on the Clarithromycin page.
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