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Generic Name: Cephalexin
Brand Name(s): Keflex
Information updated: April 1, 2000
Overview
Keflex belongs to a class of potent antibiotics called cephalosporins. It is one of the first of these to become available generically and is now often prescribed as cephalexin.
This drug works against a wide variety of germs, including those that cause infections of the skin, lungs, throat, prostate, urinary tract, bones, and ears.
Cephalosporins are broad spectrum medicines that were originally discovered in one of the world's most unlikely locations.
A fungus found close to a sewer outlet along the coast of Sardinia turned out to cure a number of nasty infections. From this chance observation many extraordinary antibiotics have been developed.
Side Effects and Interactions
Side effects from cephalosporin-type antibiotics are generally mild. Nevertheless, cephalexin can cause a range of digestive tract disorders.
Indigestion, stomach pain, nausea, vomiting and diarrhea have been reported. If diarrhea becomes severe contact your physician, as it may be a warning of drug-induced colitis.
Other infrequent reactions to be aware of include rash, itching, vaginitis, headache, confusion, joint pain, fatigue and dizziness.
Cephalexin may affect laboratory test results. Liver enzymes may become elevated and false-positive results may show up during certain diabetes tests. Make sure that the laboratory personnel are aware you are taking cephalexin if you have blood drawn.
And remember to report any symptoms or suspected side effects of cephalexin to your physician promptly.
Special Precautions
If you are allergic to penicillin-type antibiotics, alert your physician immediately. Some people who are sensitive to penicillin may also react to cephalexin.
Symptoms such as breathing difficulty, wheezing, sneezing, hives, itching, and skin rash require immediate emergency treatment.
Life-threatening anaphylactic shock may produce an inability to breathe and cardiovascular collapse and can occur within minutes of exposure.
People with kidney problems should receive cephalexin only under careful medical supervision as the dosage will most likely have to be modified to prevent toxicity.
Taking the Medicine
Although this antibiotic is absorbed more efficiently when it is taken on an empty stomach, the pills can be swallowed with food, especially if they upset your stomach.
Joe Graedon is a pharmacologist. Teresa Graedon holds a doctorate in medical anthropology and is a nutrition expert. Their syndicated radio show can be heard on public radio.
© 2000