Generic Name: cephalexin

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 purposes other than those listed in this medication guide.

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What is the price of this medication and similar alternatives?

Pricing information provided by drugstore.com.

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What are the possible side effects of cephalexin?

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 are more likely to occur, such as:

• mild nausea, vomiting, diarrhea;

• dizziness, tired feeling;

• joint pain; or

• vaginal itching or discharge.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

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How should I take cephalexin?
Take the medication exactly as it was prescribed for you. Do not use the medication in larger amounts, or use it for longer than recommended by your doctor. Follow the instructions on your prescription label. Take cephalexin with a full glass of water. Measure the liquid form of cephalexin with a special dose-measuring spoon or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one. Take this medication for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Cephalexin will not treat a viral infection such as the common cold or flu.

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What is the most important information I should know about cephalexin?
Do not use this medication if you are allergic to cephalexin, or to similar antibiotics, such as Ceclor, Ceftin, Cefzil, Duricef, Fortaz, Omnicef, Spectracef, Suprax, and others. Take this medication for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Cephalexin will not treat a viral infection such as the common cold or flu.

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What happens if I miss a dose?
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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What other drugs will affect cephalexin?
Before using cephalexin, tell your doctor if you are using any of the following drugs: a blood thinner such as warfarin (Coumadin); meftormin (Fortamet, Glucophage, Riomet, Actoplus, Avandamet, Metaglip); or probenecid (Benemid). If you are using any of these drugs, you may not be able to use cephalexin, or you may need dosage adjustments or special tests during treatment. There may be other drugs not listed that can affect 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.

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Can I take this if I am pregnant or trying to get pregnant or if I am breastfeeding?

Cephalexin has been assigned to pregnancy category B by the FDA. Animal studies have failed to reveal evidence of fetotoxicity or teratogenicity. There are no controlled data in human pregnancy. However, the drug has been used in various stages of pregnancy without evidence of fetal harm. Cephalexin should only be given during pregnancy when need has been clearly established.

Cephalexin crosses the human placenta. In one study of 30 pregnant women who were given cephalexin 1 gram orally once, the average peak umbilical cord and amniotic drug levels were 11.3 (four hours after dosing) and 13.2 mcg/mL (six hours after dosing), respectively. The Michigan Medicaid surveillance study showed a possible association between cephalexin and congenital defects. This report is a summary of information from two studies, one in which 1,705 of 104,000 pregnant women from 1980 to 1983, and one in which 3,613 of 229,000 pregnant women from 1985 to 1992 received cephalexin. In the first study, 127 total defects and 19 cardiovascular defects were observed (122 and 16 were expected, respectively). In the second study, 176 total defects were observed (154 expected), of which 44 were cardiovascular in nature (36 expected). Cleft palate was observed once in the first study and 11 times in the second. These data support an association between cephalexin and congenital defects, although other causes, such as the underlying disease(s) of the mother and concomitant drug therapy are unaccounted for.

Cephalexin is excreted into human milk in small amounts, although adverse effects are unlikely in the nursing infant. Other cephalosporins have been classified as compatible with breast-feeding by the American Academy of Pediatrics.

In one study of six women who received cephalexin 1 gram orally, the average peak milk level was 0.51 mcg/mL between four and five hours after dosing. The average milk-to-maternal plasma drug level ratios were 0.008, 0.021, and 0.140 at 1, 2, and 3 hours after dosing, respectively. While these levels are extremely low, some experts warn of possible unknown direct risk to breast-feeding infants, modification of neonatal bowel flora, and difficulty in interpreting culture results in the evaluation of a suspected infection.

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Who should NOT use this medication?

• Known hypersensitivity to cephalexin or other cephalosporins.

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What happens if I overdose?
Seek emergency medical attention if you think you have used too much of this medicine. Symptoms of a cephalexin overdose may include nausea, vomiting, stomach pain, diarrhea, and blood in your urine.

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What should I discuss with my healthcare provider before taking cephalexin?
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 this 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

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Can I stop taking the medication if I feel better?
If you have been diagnosed with a disease for which an antibiotic is needed, you must complete the prescribed course of treatment. Even if you start to feel better, do not skip any doses and remember to take the medication until it is all gone.

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I am on so many medications; do I have to take them all?
This is called polypharmacy—many different medications being used at the same time by one person. Sometimes, being on multiple medications is acceptable and appropriate but at other times it may be problematic. If you are receiving your medications from multiple physicians you need to ensure that they all know what medications you are taking. The best way to do this is to make a list of all the medications you are currently using, including all nutritional supplements, homeopathic remedies, vitamins and over-the-counter drugs (if possible, also include all the diseases you have been diagnosed with). Give a copy to every doctor who takes care of you so they have it on file, this way they can avoid duplicating medications and perhaps even try to consolidate some. After every doctor's visit remember to update the list accordingly. Also, as much as you possibly can, try to use the same pharmacy to fill all your prescriptions, this way any potential drug interactions can be caught and averted.

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Where can I get more information?
More Information

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