Drug Interaction Report

Lomitapide and Ketoconazole Topical: Interaction Details

A pharmacist-reviewed analysis of the Lomitapide and Ketoconazole Topical interaction: the documented clinical effects, severity rating, onset, mechanism, and management considerations, with cited references throughout.

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Lomitapide

No brand names on record
+

Ketoconazole Topical

Extina® Foam Ketozole® Cream Kuric Nizoral AD® Shampoo Nizoral® Cream Nizoral® Shampoo Xolegel®
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
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Interaction severity
Contraindicated
These should generally not be used together.
How we grade severity & evidence

Severity levels

  • Contraindicated: These should generally not be used together.
  • Major: Potentially serious — often needs a change or close monitoring.
  • Moderate: Can be significant — usually manageable with monitoring.
  • Minor: Usually limited clinical impact.

Evidence grades

  • Established: Well documented — supported by controlled studies or strong clinical data.
  • Probable: Good supporting evidence, though not definitively proven.
  • Suspected: Some evidence suggests this interaction, but it is not well established.
  • Possible: Limited or conflicting evidence; the interaction may occur.
  • Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.

Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.

Of 83 documented Lomitapide interactions, 5 are rated contraindicated — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
Onset
unspecified
Evidence
probable
Severity
Contraindicated

What happens

Increased lomitapide exposure

Interaction Deep Dive

Concomitant use of lomitapide (a CYP3A4 substrate) with a strong CYP3A4 inhibitor is contraindicated, as coadministration may result in increased exposure of lomitapide. In a study with concomitant use of a strong CYP3A4 inhibitor (ketoconazole 200 mg twice daily for 9 days) and lomitapide (60 mg daily), lomitapide AUC was increased by 27-fold and Cmax was increased by 15-fold. One patient had markedly elevated transaminases (ie, ALT and AST) within days of initiating clarithromycin, a strong CYP3A4 inhibitor, during lomitapide clinical trials. If treatment with a strong CYP3A4 inhibitor is unavoidable, discontinue lomitapide during the course of treatment1.

Why it happens (mechanism)

Inhibition of CYP3A4-mediated metabolism of lomitapide

Literature reports

2 reports — tap to read

a) During lomitapide clinical trials, a patient with homozygous familial hypercholesterolemia (HoFH) had markedly elevated transaminases (ALT, 24 times ULN; AST, 13 times ULN) within days of initiating clarithromycin, a strong CYP3A4 inhibitor 1.

b) In a drug interaction study, concomitant use of a strong CYP3A4 inhibitor (ketoconazole 200 mg twice daily for 9 days) and lomitapide (60 mg daily) increased lomitapide AUC and Cmax by 27-fold and by 15-fold, respectively 1.

Common questions

Can I take Lomitapide and Ketoconazole Topical together?

Increased lomitapide exposure Always confirm with your pharmacist or prescriber before making any change.

How serious is the Lomitapide and Ketoconazole Topical interaction?

It is rated contraindicated. These should generally not be used together.

How quickly could this interaction happen?

The documented onset is "unspecified". The timing of this interaction is not well characterized.

How strong is the evidence for this interaction?

The evidence is graded "probable". Good supporting evidence, though not definitively proven.

Questions for your pharmacist

  • Does my dose of Lomitapide or Ketoconazole Topical need adjusting while I take them together?
  • What symptoms should prompt me to call you or my prescriber right away?
  • Does the timing of my doses matter for this combination?
  • Is there a safer alternative to one of these medications for me?

References (1)

  1. Product Information: JUXTAPID® oral capsules, lomitapide oral capsules. Chiesi USA, Inc. (per Manufacturer), Cary, NC, 2026. DailyMed
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Lomitapide

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Ketoconazole Topical

Keep reading about Ketoconazole Topical

All Ketoconazole Topical interactions (546) Ketoconazole Topical drug information
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Beyond drug–drug

These medications also interact with supplements

Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:

Lomitapide + Activated Charcoal Beer Grapefruit Siberian Cocklebur St. John's Wort Wine Acacia Rigidula Adrafinil + 160 more

major · moderate · minor — check everything you take with our drug–supplement interaction checker.

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This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.