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Medications and Drugs

Brand Names: Ancef, Kefzol

Generic Name: cefazolin (injection) (Pronunciation: sef A zoe lin)

What is cefazolin (Ancef, Kefzol)?

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

What are the possible side effects of cefazolin (Ancef, Kefzol)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have a serious side effect such as:

  • diarrhea that is watery or bloody;
  • white patches or sores inside your mouth or on your lips;
  • skin rash, bruising, severe tingling, numbness, pain, muscle weakness;
  • fever, swollen glands, body aches, flu symptoms;
  • unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;
  • urinating less than usual or not at all;
  • seizure (black-out or convulsions); or
  • severe skin reaction -- fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Less serious side effects may include:

  • pain, swelling, or a hard lump where the injection was given;
  • stomach pain, nausea, vomiting, loss of appetite;
  • skin rash or itching;
  • rectal itching; or
  • vaginal itching or discharge.

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.

What is the most important information I should know about cefazolin (Ancef, Kefzol)?

You should not use this medication if you have ever had a severe allergic reaction to any type of cephalosporin antibiotic or any type of penicillin antibiotic.

Before using cefazolin, tell your doctor if you are allergic to any drugs (especially penicillins), or if you have kidney disease, liver disease, or a stomach or intestinal disorder such as colitis.

Before using cefazolin, tell your doctor if you are also using probenecid (Benemid).

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 common cold or flu.

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

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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