cephalexin, Keflex (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

SIDE EFFECTS: The most common side effects of cephalexin are:

Individuals who are allergic to penicillin may also be allergic to cephalexin. Serious but rare reactions include seizures, severe allergic reactions (anaphylaxis), and low platelet or red blood cell count.

Cephalexin, like almost all antibiotics, may cause mild or severe cases of pseudomembranous colitis, a mild to severe inflammation of the colon. Antibiotics, including cephalexin alter the types of bacteria in the colon and permit overgrowth of a bacterium called Clostridium difficile. Studies indicate that toxins produced by Clostridium difficile are a primary cause of pseudomembranous colitis.

PRESCRIPTION: Yes

GENERIC AVAILABLE: Yes

PREPARATIONS:

  • Tablets: 250 and 500 mg.
  • Capsules: 250, 500 and 750 mg.
  • Powder for Suspension: 125 and 250 mg/5 ml.

STORAGE: Tablets and capsules should be stored at room temperature, 15 C to 30 C (59 F to 86 F). Suspensions should be refrigerated and discarded 14 days after they have been prepared from the powder.

DOSING: The dose of cephalexin for adults is 1 to 4 grams in divided doses. The usual adult dose is 250 mg every 6 hours. Some infections may be treated with 500 mg every 12 hours. Children are treated with 25-100 mg/kg/day in divided doses. The dosing interval may be every 6 or 12 hours depending on the type and seriousness of the infection.

Medically Reviewed by a Doctor on 3/27/2015


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