Drug Interaction Report

Ketoconazole Topical and Sucralfate: Interaction Details

A pharmacist-reviewed analysis of the Ketoconazole Topical and Sucralfate 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

Ketoconazole Topical

Extina® Foam Ketozole® Cream Kuric Nizoral AD® Shampoo Nizoral® Cream Nizoral® Shampoo Xolegel®
+

Sucralfate

Carafate Carafate®
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
Major
Potentially serious — often needs a change or close monitoring.
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 546 documented Ketoconazole Topical interactions, 380 are rated major — 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
rapid
Evidence
theoretical
Severity
Major

What happens

Decreased ketoconazole exposure

Interaction Deep Dive

Concurrent use of ketoconazole and sucralfate is not recommended, as coadministration may reduce ketoconazole plasma concentrations leading to a loss of ketoconazole therapeutic effect1. In 1 clinical study, the AUC of ketoconazole decreased by about 20% with concomitant use with sucralfate. This type of reaction has also been reported with H-2 blockers 321. If concurrent use is clinically warranted, carefully monitor the patient for continued antifungal efficacy.

Why it happens (mechanism)

Decreased ketoconazole absorption

Literature reports

1 report — tap to read

a) A decrease in peak-drug concentration and an increase in time-to-peak concentration of ketoconazole was observed when concomitantly administered with sucralfate 1 gram in 5 of 6 volunteers receiving a single dose of ketoconazole 400 mg. Also, sucralfate decreased the bioavailability of ketoconazole (ie, a decrease in the mean AUC occurred) 2.

Common questions

Can I take Ketoconazole Topical and Sucralfate together?

Decreased ketoconazole exposure Always confirm with your pharmacist or prescriber before making any change.

How serious is the Ketoconazole Topical and Sucralfate interaction?

It is rated major. Potentially serious — often needs a change or close monitoring.

How quickly could this interaction happen?

The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.

How strong is the evidence for this interaction?

The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.

From our Q&A

Real reader questions about these medications, each personally answered by our pharmacist:

Questions for your pharmacist

  • Does my dose of Ketoconazole Topical or Sucralfate 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 (3)

  1. Product Information: NIZORAL(R) oral tablets, ketoconazole oral tablets. Janssen Pharmaceuticals (per FDA), Titusville, NJ, 2013. DailyMed
  2. Piscitelli SC, Goss TF, Wilton JH, et al: Effects of ranitidine and sucralfate on ketoconazole bioavailability. Antimicrob Agents Chemother 1991; 35:1765-1771. PubMed
  3. Goss TF: Evaluation of ketoconazole bioavailability interactions with sucralfate and ranitidine using gastric pH monitoring (abstract). Clin Pharmacol Ther 1991; 49:128.
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Ketoconazole Topical

Keep reading about Ketoconazole Topical

All Ketoconazole Topical interactions (546) Ketoconazole Topical drug information
Also serious with: Colchicine Conivaptan Crizotinib Dabrafenib
Sucralfate

Keep reading about Sucralfate

All Sucralfate interactions (18) Sucralfate drug information
Also serious with: Digoxin Dolutegravir
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:

Sucralfate + Activated Charcoal Coffee Charcoal European Mandrake Glucomannan Guar Gum Gum Arabic Slippery Elm Tragacanth + 9 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.