What is cephalexin?

Cephalexin is in a group of drugs called cephalosporin antibiotics. Cephalexin fights bacteria in the body.

Cephalexin is used to treat infections caused by bacteria, including upper respiratory infections, ear infections, skin infections, and urinary tract infections.

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

Precautions

Do not use this medication if you are allergic to cephalexin, or to other cephalosporin antibiotics, such as:

  • cefaclor (Ceclor);
  • cefadroxil (Duricef);
  • cefdinir (Omnicef);
  • cefditoren (Spectracef);
  • cefixime (Suprax);
  • cefprozil (Cefzil);
  • ceftazidime (Fortaz); or
  • cefuroxime (Ceftin).

Before using cephalexin, tell your doctor if you are allergic to any drugs (especially penicillins), or if you have:

  • kidney disease;
  • liver disease;
  • a stomach or intestinal disorder such as colitis;
  • diabetes; or
  • if you are malnourished.

If you have any of these conditions, you may need a dose adjustment or special tests to safely take cephalexin.

The oral suspension (liquid) form of cephalexin may contain sugar. This may affect you if you have diabetes.

FDA pregnancy category B. This medication is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Cephalexin can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or has blood in it, call your doctor. Do not use any medicine to stop the diarrhea unless your doctor has told you to.

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Instructions

Seek emergency medical attention if you think you have used too much of this medicine.

Overdose symptoms may include nausea, vomiting, stomach pain, diarrhea, and blood in your urine.

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

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Side Effects

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 any of these serious side effects:

  • diarrhea that is watery or bloody;
  • seizure (convulsions);
  • fever, sore throat, and headache with a severe blistering, peeling, and red skin rash;
  • pale or yellowed skin, dark colored urine, fever, confusion or weakness;
  • easy bruising or bleeding, unusual weakness;
  • confusion, agitation, hallucinations (seeing things that are not there); or
  • urinating less than usual or not at all.

Less serious side effects may include:

  • mild nausea, vomiting, diarrhea;
  • dizziness, tired feeling;
  • joint pain; 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. You may report side effects to FDA at 1-800-FDA-1088.

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Interactions

Before using cephalexin, tell your doctor if you are using any of the following drugs:

  • a blood thinner such as warfarin (Coumadin);
  • metformin (Fortamet, Glucophage, Riomet, Actoplus, Avandamet, Metaglip); or
  • probenecid (Benemid).

This list is not complete and there may be other drugs that can interact with cephalexin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Other Names

Biocef, Keflex, Panixine, Zartan, and cephalexin

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Disclaimer

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2004 Cerner Multum, Inc. Version 2.05. Revision date 8/23/04

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