Drug Interaction Report

Cimetidine and Cefpodoxime: Interaction Details

A pharmacist-reviewed analysis of the Cimetidine and Cefpodoxime 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

Cimetidine

Tagamet
+

Cefpodoxime

Banan® Cefpoderm Dermaceph Simplicef Vantin®
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
Moderate
Can be significant — usually manageable with 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 83 documented Cimetidine interactions, 22 are rated moderate — including this one.
Onset
rapid
Evidence
probable
Severity
Moderate

What happens

Decreased cefpodoxime effectiveness

Interaction Deep Dive

Drugs that raise gastric pH, such as H2 blockers, reduce cefpodoxime absorption2.

Why it happens (mechanism)

Decreased cefpodoxime absorption

Literature reports

3 reports — tap to read

a) Administration of ranitidine interferes with the oral absorption of cefpodoxime proxetil. One study showed that gastric pH was inversely related to peak plasma cefpodoxime concentrations and AUCs. Administration of cefpodoxime with ranitidine 150 mg twice a day significantly reduced the peak plasma concentration and AUC of cefpodoxime 1. The clinical significance of this interaction is unknown.

b) Drugs that raise gastric pH reduce cefpodoxime absorption. A single dose of famotidine 40 mg given one hour before cefpodoxime was shown to decrease cefpodoxime AUC by 40% 2.

c) Concomitant administration of cefpodoxime and H2 blockers reduces peak plasma levels of cefpodoxime by 24% to 42% and the extent of absorption by 27% to 32%, respectively. The rate of absorption is not altered by these concomitant medications 3.

Common questions

Can I take Cimetidine and Cefpodoxime together?

Decreased cefpodoxime effectiveness Always confirm with your pharmacist or prescriber before making any change.

How serious is the Cimetidine and Cefpodoxime interaction?

It is rated moderate. Can be significant — usually manageable with 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 "probable". Good supporting evidence, though not definitively proven.

Questions for your pharmacist

  • Does my dose of Cimetidine or Cefpodoxime 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 anything you'd monitor while I'm on both?

References (3)

  1. Hughes GS, Heald DL, Barker KB, et al: The effects of gastric pH and food on the pharmacokinetics of a new oral cephalosporin, cefpodoxime proxetil. Clin Pharmacol Ther 1989; 46:674-685. DOI
  2. Saathoff N, Lode H, Neider K, et al: Pharmacokinetics of cefpodoxime proxetil and interactions with an antacid and an H2 receptor antagonist. Antimicrob Agents Chemother 1992; 36:796-800. PubMed
  3. Product Information: Vantin(R), cefpodoxime. Pharmacia & Upjohn Company, Kalamazoo, MI, 2000. DailyMed
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Cimetidine

Keep reading about Cimetidine

All Cimetidine interactions (83)
Also serious with: Dofetilide Colchicine Octreotide Injection Meloxicam Injection
Cefpodoxime

Keep reading about Cefpodoxime

All Cefpodoxime interactions (26) Cefpodoxime drug information
Also serious with: Levonorgestrel Intrauterine System Estradiol Topical Estradiol Transdermal Patch Furosemide Injection
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:

Cimetidine + Activated Charcoal Pu-erh Tea St. John's Wort Adrafinil African Wild Potato Banderol Beer Bitter Melon + 87 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.