Cephalexin (Keflex®)

Overview

·  Cephalexin is an antibiotic of the cephalosporin class. It is related to the penicillin drugs in how it kills bacteria, but cephalosporins have a much broader range of activity against bacteria than penicillins.

·  Cephalexin will prevent the bacteria from forming an adequate and protective cell wall. This results in instability and subsequent death of the bacteria. 

·  Cephalexin is a prescription drug and can only be obtained from a veterinarian or by prescription from a veterinarian.

·  This drug is not approved for use in animals by the Food and Drug Administration but it is prescribed legally by veterinarians as an extra-label drug.

Brand Names and Other Names

·  This drug is registered for use in humans only.

·  Human formulations: Keflex® (Dista)and generic forms 

·  Veterinary formulations: None

Uses of Cephalexin

·  Cephalexin is used in both dogs and cats to treat a variety of bacterial infections, including skin infections, wound infections, bone infections, pneumonia, and bladder infections. 

·  Cephalexin is similar to the veterinary drug cefadroxil, and veterinarians often use the two drugs interchangeably. The drugs have equal effectiveness.

·  Cephalexin is not effective against infections caused by parasites (intestinal worms), mites, viruses or fungi.

Precautions and Side Effects

·  While generally safe and effective when prescribed by a veterinarian, cephalexin can cause side effects in some animals.

·  Cephalexin should not be used in animals with known hypersensitivity or allergy to the drug.

·  If a pet is already sensitive to allergy or vomiting from other cephalosporin drugs (cefadroxil) or penicillins (amoxicillin, ampicillin), cross-reaction with cephalexin is possible.

·  Cephalexin may interact with other medications. Consult with your veterinarian to determine if other drugs your pet is receiving could interact with cephalexin. Such drugs include certain other antibiotics.

·  The most common side effect in animals is vomiting shortly after administration. It is usually not a sign of serious disease, but indicates that the pet is sensitive to this drug.

·  It is not unusual for some animals to develop diarrhea from orally administered antibiotics such as cephalexin. However, this has not been a common complaint with cephalexin.

How Cephalexin Is Supplied

·  Cephalexin is available in 250 mg and 500 mg capsules, 250 mg and 500 mg tablets and an oral suspension in the strength of 25 mg/ml and 50 mg/ml.

Dosing Information

·  Medication should never be administered without first consulting your veterinarian. 

·  The usual dose is 10 to 15 mg per pound (22 to 30 mg/kg) every 8 to 12 hours orally for dogs and cats. 

·  The duration of administration depends on the condition being treated, response to the medication and the development of any adverse effects. Be certain to complete the prescription unless specifically directed by your veterinarian. Even if your pet feels better, the entire treatment plan should be completed to prevent relapse or prevent the development of resistance.