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Cefazolin (injection)

Generic Name: cefazolin (injection) (sef A zoe lin)
Brand Name: Ancef, Kefzol

Medically reviewed on December 8, 2017.

What is cefazolin?

Cefazolin is a cephalosporin (SEF a low spor in) antibiotic. It works by fighting bacteria in your body.

Cefazolin is used to treat many kinds of bacterial infections, including severe or life-threatening forms. Cefazolin is also used to help prevent infection in people having certain types of surgery.

Cefazolin may also be used for purposes not listed in this medication guide.

Important Information

You should not use cefazolin if you have ever had a severe allergic reaction to any type of cephalosporin antibiotic (Omnicef, Keflex, and others).

Before taking this medicine

You should not use this medicine if you have ever had a severe allergic reaction to cefazolin or any other cephalosporin antibiotic, such as:

To make sure cefazolin is safe for you, tell your doctor if you have:

  • kidney disease;

  • liver disease;

  • a stomach or intestinal disorder such as colitis; or

  • if you are allergic to any type of penicillin.

Cefazolin is not expected to harm an unborn baby. Tell your doctor if you are pregnant.

Cefazolin can pass into breast milk, but effects on the nursing baby are not known. Tell your doctor if you are breast-feeding.

How is cefazolin given?

Cefazolin is injected into a vein through an IV.

A healthcare provider will give you this injection when cefazolin is used to prevent infection from surgery.

You may be shown how to use an IV at home to treat an infection. Do not give yourself this medicine if you do not understand how to use the injection and properly dispose of needles, IV tubing, and other items used.

Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Cefazolin may need to be mixed with a liquid (diluent) before using it. If you are using the injections at home, be sure you understand how to properly mix and store the medicine.

Use this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics. Cefazolin will not treat a viral infection such as the flu or a common cold.

This medicine can cause unusual results with certain lab tests for glucose (sugar) in the urine. Tell any doctor who treats you that you are using cefazolin.

Store unmixed cefazolin at room temperature, away from moisture, heat, and light.

After mixing cefazolin with a diluent, store the mixture in the refrigerator. Do not freeze.

Take the mixture out of the refrigerator and allow it to reach room temperature before injecting your dose. Mixed medicine must be used within a certain number of days once it reaches room temperature. Carefully follow all mixing and storage instructions for this medicine.

Do not use the medicine if it has changed colors or has particles in it. Call your pharmacist for new medication.

Use a disposable needle and syringe only once. Follow any state or local laws about throwing away used needles and syringes. Use a puncture-proof "sharps" disposal container (ask your pharmacist where to get one and how to throw it away). Keep this container out of the reach of children and pets.

What happens if I miss a dose?

Call your doctor for instructions if you miss a dose of cefazolin.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using cefazolin?

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.

Cefazolin side effects

Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning in your eyes, skin pain, red or purple skin rash that spreads and causes blistering and peeling).

Call your doctor at once if you have:

  • severe stomach pain, diarrhea that is watery or bloody;

  • white patches or sores inside your mouth or on your lips;

  • fever, swollen glands, rash or itching, joint pain, or general ill feeling;

  • seizure (convulsions); or

  • liver problems--upper stomach pain, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect cefazolin?

Other drugs may interact with cefazolin, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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