Drug Interaction Report

Cefdinir and Furosemide: Interaction Details

A pharmacist-reviewed analysis of the Cefdinir and Furosemide 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

Furosemide

Disal Furoscix Lasix Salix - substance
+

Cefdinir

Omnicef®
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
LinkedIn
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 42 documented Cefdinir interactions, 27 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
unspecified
Evidence
theoretical
Severity
Major

What happens

Increased risk of cephalosporin-induced nephrotoxicity

Interaction Deep Dive

Concomitant use of furosemide with cephalosporins may increase the risk of cephalosporin-induced nephrotoxicity even in the setting of minor or transient renal impairment. Hence, if coadministered monitor for changes in renal function12.

Why it happens (mechanism)

Unknown

Common questions

Can I take Cefdinir and Furosemide together?

Increased risk of cephalosporin-induced nephrotoxicity Always confirm with your pharmacist or prescriber before making any change.

How serious is the Cefdinir and Furosemide interaction?

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

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 "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 Cefdinir or Furosemide 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 (2)

  1. Product Information: FUROSCIX(R) subcutaneous injection, furosemide subcutaneous injection. scPharmaceuticals Inc (per FDA), Burlington, MA, 2025. DailyMed
  2. Product Information: LASIX® ONYU subcutaneous injection, furosemide subcutaneous injection. SQ Innovation, Inc (per manufacturer), Burlington, MA, 2025. DailyMed
Was this write-up helpful?
Furosemide

Keep reading about Furosemide

All Furosemide interactions (105)
Also serious with: Desmopressin Nasal Irbesartan Meloxicam Diclofenac Topical (Arthritis Pain)
Cefdinir

Keep reading about Cefdinir

All Cefdinir interactions (42) Cefdinir drug information
Also serious with: Azathioprine Methotrexate Injection Levonorgestrel Intrauterine System Exenatide 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:

Furosemide + Activated Charcoal American Hellebore American Mistletoe Asarabacca Lithium Oleander Siberian Cocklebur Tyramine + 219 more
Cefdinir + Activated Charcoal Asarabacca Siberian Cocklebur African Wild Potato Aristolochia Bacillus Coagulans Bacillus Subtilis Banderol + 52 more

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

Check another combination

Our instant two-drug interaction checker is almost here.

Coming soon

The instant two-drug checker is on its way.

In the meantime, browse the directory below to look up any drug and see its documented interactions.

Still have questions about this combination?

Every question gets a real answer from a licensed pharmacist — free, and usually within a day.

Ask the pharmacist
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.