Cefazolin: uses, dosing, side effects & brands
Cefazolin is a cephalosporin antibacterial sold in the U.S. under 5 brand and generic names, for human bites, bacterial endocarditis and escherichia coli infections. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Drug class
- Cephalosporin Antibacterial
- Treats (across its forms)
- Human Bites, Bacterial Endocarditis and Escherichia Coli Infections
- Available as
- Injectable · Solution
- Sold as
- 5 products — Ancef, Ancef in Dextrose 5% in Plastic Container and Ancef in Sodium Chloride 0.9% in Plastic Container, and others
- Prescription?
- Prescription only
- Generic available?
- Yes
- What the pharmacy pays
- about $30 for a 30-count supply — not your price
How Cefazolin and Dextrose is dosed
From the FDA label for Cefazolin and Dextrose (application NDA050779). Other cefazolin products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
If a dose of Cefazolin for Injection and Dextrose Injection is required that does not equal 1 gram, 2 grams or 3 grams, this product is not recommended for use and an alternative formulation of cefazolin should be considered. ( 2.1 ) For intravenous use only administered over approximately 30 minutes. ( 2.1 ) Recommended Dosing Schedule in Adult Patients with CLcr Greater Than or Equal To 55 mL/min. ( 2.1 , 2.2 and 2.3 ) Site and Type of Infection Dose Frequency Moderate to severe infections 500 milligram (mg) to 1 gram every 6 to 8 hours Mild infections caused by susceptible gram-positive cocci 250 mg to 500 mg every 8 hours Acute, uncomplicated urinary tract infections 1 gram every 12 hours Pneumococcal pneumonia 500 mg every 12 hours Severe, life-threatening infections (e.g., endocarditis, septicemia) In rare instances, doses of up to 12 grams of cefazolin per day have been used. 1 gram to 1.5 grams every 6 hours Perioperative prophylaxis less than 120 kg: 1 gram to 2 grams 1/2 to 1 hour prior to start of surgery greater than or equal to 120 kg: 3 grams 500 mg to 1 gram additional dose during lengthy operative procedures 500 mg to 1 gram every 6 to 8 hours for 24 hours postoperatively Recommended Dosing Schedule in Pediatric Patients with CLcr Greater than or Equal to 70 mL/min. ( 2.1 , 2.2 , and 2.3 ) Site and Type of Infection Dose Frequency Moderate to severe infections…
Everything below is the FDA label for Cefazolin and Dextrose (solution). Cefazolin is also sold as injectable, and those are different medicines to take — follow the label for the one you were prescribed.
Cefazolin and Dextrose side effects
The following serious adverse reactions to Cefazolin for Injection and Dextrose Injection are described below and elsewhere in the labeling: Hypersensitivity Reactions to Cefazolin, Cephalosporins, Penicillins, or Other Beta-lactams [see Warnings and Precautions (5.1) ] Seizures in Patients with Renal Impairment [see Warnings and Precautions (5.2) ] Clostridioides difficile -associated Diarrhea [see Warnings and Precautions (5.3) ] Prothrombin Activity [ see Warnings and Precautions (5.5) ] Adult and Pediatric Patients : Most common adverse reactions: gastrointestinal (nausea, vomiting, diarrhea), and allergic reactions (anaphylaxis, urticaria, skin rash). ( 6 ) Pediatric Patients with Perioperative Prophylaxis: The most frequently reported adverse reactions (incidence ≥ 5%) were nausea, infusion site pain, and headache. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact B. Braun Medical Inc. at 1-800-854-6851 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The following adverse reactions were reported from clinical trials: Gastrointestinal: Diarrhea, oral candidiasis (oral thrush),…
Who shouldn’t take Cefazolin and Dextrose
Hypersensitivity to cefazolin or other cephalosporin class antibacterial drugs, penicillins, or other beta-lactams ( 4.1 ) 4.1 Hypersensitivity to Cefazolin or the Cephalosporin Class of Antibacterial Drugs, Penicillins, or Other Beta-lactams Cefazolin for Injection and Dextrose Injection is contraindicated in patients who have a history of immediate hypersensitivity reactions (e.g., anaphylaxis, serious skin reactions) to cefazolin or the cephalosporin class of antibacterial drugs, penicillins, or other beta-lactams [see Warnings and Precautions (5.1) ] .
Cefazolin and Dextrose drug interactions
The renal excretion of cefazolin is inhibited by probenecid. Co-administration of probenecid with Cefazolin for Injection and Dextrose Injection is not recommended. Probenecid: The renal excretion of cefazolin is inhibited by probenecid. Co-administration of probenecid with cefazolin for injection is not recommended. ( 7 )
Every cefazolin product we track (5)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
| # | Drug | Rating | Type | Form | Generic? | Pharmacy pays | |
|---|---|---|---|---|---|---|---|
| 1 | 70/100 | Prescription | Injectable | Generic | $30 | View → | |
| 2 | Not yet rated | Prescription | Injectable | Generic | $30 | View → | |
| 3 | Not yet rated | Prescription | Injectable | Generic | $30 | View → | |
| 4 | Not yet rated | Prescription | Solution | Generic | $30 | View → | |
| 5 | Not yet rated | Prescription | Injectable | Generic | $30 | View → |
Cefazolin recalls
From the FDA Enforcement database. A recall covers specific lots — not the drug as a whole.
How long cefazolin keeps
The date on a sealed pack is not the only one: some cefazolin labels start a second clock once the product is opened or mixed, as short as 4 hours.
Does cefazolin expire? The in-use limits and storage rules from its labelsCefazolin and breastfeeding
From LactMed, the US National Library of Medicine’s Drugs and Lactation Database — quoted, not rewritten.
Full LactMed record for cefazolin: levels in milk, effects in breastfed infants, and the drugs it would consider insteadLimited information indicates cefazolin produces low levels in milk that are not expected to cause adverse effects in breastfed infants. Occasionally disruption of the infant's gastrointestinal flora, resulting in diarrhea or thrush have been reported with cephalosporins, but these effects have not been adequately evaluated. Cefazolin is acceptable in nursing mothers.
National Institute of Child Health and Human Development, record revised November 15, 2024. LactMed states its information is not a substitute for professional judgement.
What people report to the FDA about cefazolin
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 3,054 reports naming cefazolin, and the FDA flagged 95% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- anaphylactic shock261 reports
- anaphylactic reaction156 reports
- hypotension154 reports
- pyrexia143 reports
- rash126 reports
- erythema96 reports
- anaemia93 reports
- nausea92 reports
Read these as a signal, not a rate. A report does not mean cefazolin caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 25, 2026.
Related calculators
Frequently asked questions
What is Cefazolin and Dextrose?
Cefazolin and Dextrose (Cefazolin Sodium) is a cephalosporin antibacterial used to treat Human Bites, Bacterial Endocarditis, Escherichia Coli Infections, Klebsiella Infections.
What kind of drug is cefazolin?
The FDA classifies cefazolin as a cephalosporin antibacterial. Cephalosporins kill bacteria by blocking the proteins they use to build their cell walls. Without an intact wall, the bacterium cannot hold its shape and dies, which clears the infection. If you are checking whether it is safe to combine with something else, the class is what matters — two drugs from the same class usually should not be stacked.
Can you take cefazolin with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run cefazolin against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What brand names is cefazolin sold under?
We track 5 cefazolin-containing products in the U.S.: Ancef, Ancef in Dextrose 5% in Plastic Container, Ancef in Sodium Chloride 0.9% in Plastic Container, Cefazolin and Dextrose and Cefazolin Sodium. They are the same active ingredient; they differ in form, manufacturer, price and FDA recall record.
What forms does cefazolin come in?
Across the brands we track, cefazolin is currently marketed as injectable and solution, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic cefazolin?
Yes. Our catalog lists 1 generic cefazolin product alongside the brand versions. A generic has the same active ingredient and must meet the FDA's bioequivalence standard; it usually costs less. Ask your pharmacist which one your plan covers.
Has cefazolin been recalled?
The FDA's Enforcement database lists 1 recall record whose product description mentions cefazolin. The most recent: Cefazolin for Injection (Jun 27, 2025). A recall applies to specific lots, not to the drug as a whole — check the record for the affected lot numbers.
Cite this page
- APA
- pharmaranks. (2026, July 24). Cefazolin: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/cefazolin
- MLA
- “Cefazolin: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/cefazolin.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for cefazolin on DailyMed (NIH) ↗.