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Generic name: cefotaximeSEF-oh-TAX-eem ]
Drug class: Third generation cephalosporins

Medically reviewed by on Mar 2, 2023. Written by Cerner Multum.

What is Claforan?

Claforan is a cephalosporin (SEF a low spor in) antibiotic.

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

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


You should not use Claforan if you are allergic to Claforan or another cephalosporin antibiotic (cefdinir, cefalexin, Keflex, Omnicef, and others).

Before taking this medicine

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

Tell your doctor if you have ever had:

  • an allergy to penicillin;

  • kidney disease;

  • liver disease;

  • a stomach or intestinal disorder such as colitis;

  • diabetes; or

  • heart problems.

Tell your doctor if you are pregnant or breastfeeding.

How should I use Claforan?

Claforan is injected into a muscle, or given as an infusion into a vein.

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

A healthcare provider may teach you how to properly use the medication by yourself to treat an infection.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you don't understand all instructions.

Claforan must be mixed with a liquid (diluent) before using it. You may need to further dilute the mixed medicine before injecting your dose. If you are using the injections at home, be sure you understand how to properly mix and store the medication.

Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

Use Claforan for the full prescribed length of time, even if your symptoms quickly improve. Skipping doses can increase your risk of infection that is resistant to medication. Claforan will not treat a viral infection such as the flu or a common cold.

This medicine can affect the results of certain medical tests. Tell any doctor who treats you that you are using Claforan.

Store the unmixed medicine at cool room temperature (not above 77 degrees F).

Mixed medicine must be used within a certain number of hours or days, depending on the type of diluent used in the mixture. Carefully follow all mixing and storage instructions for Claforan.

After mixing Claforan with a diluent, you may need to store the mixture in a refrigerator and use it within a certain number of days.

What happens if I miss a dose?

Use the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not use two doses at one time.

If you are receiving this medicine at a clinic, call your doctor if you miss an appointment for your injection.

What happens if I overdose?

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

Overdose symptoms may include weakness, cold feeling, pale skin, blue lips, or seizure (convulsions).

What should I avoid while using Claforan?

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.

Claforan 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).

Claforan may cause serious side effects. Call your doctor at once if you have:

  • severe stomach pain, diarrhea that is watery or bloody (even if it occurs months after your last dose);

  • burning, irritation, or skin changes where the injection was given;

  • dark urine, jaundice (yellowing of the skin or eyes);

  • a seizure;

  • fever, chills, tiredness; or

  • easy bruising, unusual bleeding, pale skin, cold hands and feet.

Common side effects of Claforan may include:

  • pain, bruising, swelling, or other irritation where the injection was given;

  • diarrhea;

  • fever; or

  • rash, itching.

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 other drugs will affect Claforan?

Tell your doctor about all your other medicines, especially:

  • another injected antibiotic; or

  • a diuretic or "water pill."

This list is not complete. Other drugs may affect Claforan, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

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.