Keflex (cephalexin) is a cephalosporin antibiotic prescribed to treat bacterial infections. Keflex is also used before dental procedures in patients identified with certain heart-related conditions to prevent bacterial infections of the heart known as endocarditis. Keflex is available as a generic drug.
Keflex dosage depends on the condition being treated. Keflex should be used with caution in patients who have kidney disease and those who report a history of penicillinallergy.
What Drugs, Substances, or Supplements Interact with Keflex?
Keflex may interact with blood thinners, metformin, or probenecid. Tell your doctor all medications and supplements you use.
Keflex During Pregnancy and Breastfeeding
There have not been adequate studies in pregnant women, so Keflex should be used in pregnancy only when it is absolutely needed. Keflex is found in breast milk and should be used with caution in breastfeeding women.
Additional Information
Our Keflex (cephalexin) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.
Keflex Consumer Information
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 eyes, skin pain, red or purple skin rash with blistering and peeling).
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);
unusual tiredness, feeling light-headed or short of breath;
easy bruising, unusual bleeding, purple or red spots under your skin;
a seizure;
pale skin, cold hands and feet;
yellowed skin, dark colored urine;
fever, weakness; or
pain in your side or lower back, painful urination.
Common side effects may include:
diarrhea;
nausea, vomiting;
indigestion, stomach 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.
Development of Drug-Resistant Bacteria [see WARNINGS
AND PRECAUTIONS]
Clinical Trials Experience
Because clinical trials are conducted under widely
varying conditions, adverse reaction rates observed in the clinical trials of a
drug cannot be directly compared to rates in the clinical trials of another
drug and may not reflect the rates observed in practice
In clinical trials, the most frequent adverse reaction
was diarrhea. Nausea and vomiting, dyspepsia, gastritis, and abdominal pain
have also occurred. As with penicillins and other cephalosporins, transient
hepatitis and cholestatic jaundice have been reported.
Other reactions have included hypersensitivity reactions,
genital and anal pruritus, genital candidiasis, vaginitis and vaginal
discharge, dizziness, fatigue, headache, agitation, confusion, hallucinations,
arthralgia, arthritis, and joint disorder. Reversible interstitial nephritis
has been reported. Eosinophilia, neutropenia, thrombocytopenia, hemolytic anemia, and slight elevations in aspartate transaminase (AST) and alanine
transaminase (ALT) have been reported.
In addition to the adverse reactions listed above that
have been observed in patients treated with KEFLEX, the following adverse
reactions and other altered laboratory tests have been reported for
cephalosporin class antibacterial drugs:
&Copy; Keflex Patient Information is supplied by Cerner Multum, Inc. and Keflex Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.
