cephalexin for dogs and cats

Cat and Dog Antibiotics: Cephalexin Dosage for Pets

Content Sponsored by Chewy.

Overview of Cephalexin for Canines and Felines

Cephalexin, also known by the brand names Keflex®, Keftab®, Biocef®, and Rilexine®, is an antibiotic commonly prescribed for dogs and cats. It belongs to the cephalosporin class of drugs and is chemically related to penicillin in the way it kills bacteria, though cephalosporins generally have a broader spectrum of activity.

Cephalexin is considered a first-generation cephalosporin and works by interfering with a bacterium’s ability to form a stable, protective cell wall. Without a properly formed cell wall, bacteria become unstable and die. When given orally, cephalexin is readily absorbed, with peak blood levels typically occurring within two hours.

Like all dog antibiotics, cephalexin does not kill every type of bacteria but instead targets a specific range of organisms. It is effective against many gram-negative and anaerobic bacteria, including common pathogens such as Escherichia coli, Klebsiella, Proteus mirabilis, Pasteurella multocida, as well as many Streptococci and most Staphylococci species.

However, it is generally not effective against Aerobacter, Bacteroides, Enterococcus, Mycoplasma species, methicillin-resistant staphylococci, Pseudomonas, certain Proteus species, Rickettsia species, fungi, or viruses. Cephalexin is available by prescription only and must be obtained through a veterinarian or filled with a valid veterinary prescription.

Looking for a quick and convenient way to get your pet’s prescriptions delivered to your doorstep? Chewy’s pet pharmacy is a one-stop-shop for all of your pet care needs, offering a wide variety of prescription food and medication straight from the manufacturer, compound medications made just for your pet, and an Autoship option, so you never have to remember to order refills.

source
petplace-blog-keflex-medications-top
script
widget

Brand Names and Other Names of Cephalexin

Cephalexin is available under several alternative names and formulations, including cefalexin, cephalexin monohydrate, and cephalexin monohydrochloride. Human-labeled products include Keflex® (Dista), Cephaforte® (Jurox), Celexin, Cepexin, Cephacillin, Ceporexin, Ilium® (Troy), and various generic equivalents.

Veterinary-labeled products include Rilexine® (Virbac), Ceporex® (Intervet), Cephacare® (Animalcare LTD), Cefaseptin® (Vetoquinol), Cephorum® (Forum Animal Health), Cefabactin® (Le Vet Beheer), Petalexin® (Alfamed), Therios® (Ceva), and additional generic formulations.

Uses of Cephalexin for Dogs and Cats

In dogs and cats, cephalexin is prescribed to treat a variety of bacterial infections. These include skin infections such as pyoderma, wound infections, bone infections (osteomyelitis), pneumonia, upper respiratory tract infections, mastitis, and urinary tract infections involving the bladder. Cephalexin is similar to the veterinary antibiotic cefadroxil, and veterinarians may use the two drugs interchangeably due to their comparable effectiveness. It is important to note that cephalexin does not treat infections caused by parasites such as intestinal worms or mites, nor is it effective against viral or fungal infections.

Got questions about your pet’s prescription or health concerns in general? Chewy’s Connect with a Vet ™ service connects you directly with a licensed veterinarian to get answers to commonly asked questions, discuss health and wellness concerns, and get referrals to local vets and emergency clinics.

Precautions and Side Effects

While cephalexin is generally considered safe and effective when prescribed by a veterinarian, side effects can occur. It should not be used in animals with a known allergy or hypersensitivity to cephalexin.

Pets that have previously experienced allergic reactions to other cephalosporins, such as cefadroxil, or to penicillins like amoxicillin or ampicillin, may also have a cross-reaction to cephalexin. Signs of an allergic reaction can include rash, hives, itching, facial swelling, or difficulty breathing. Veterinary attention should be sought immediately if these symptoms occur.

The most commonly reported side effect in dogs and cats is vomiting shortly after administration. Although usually not serious, this may indicate sensitivity to the medication. Diarrhea can also develop with orally administered antibiotics, though it is not especially common with cephalexin.

Other possible side effects include decreased appetite, drooling, lethargy, increased activity or excitement, and in some cats, fever. High doses or overdoses have been associated with blood abnormalities, including neutropenia (low white blood cell counts).

Cephalexin should be used cautiously in pets with a history of seizures or epilepsy, in pregnant animals, and in those with kidney (renal) failure. Lower doses are recommended for pets with impaired kidney function. The drug appears to be safe for lactating pets.

Humans who are allergic to cephalexin or penicillin should avoid direct contact with the medication, as sensitization can occur through handling. Wearing gloves or having another household member administer the medication may be advisable.

All medications should be kept out of reach of children and pets to prevent accidental overdose. Mild overdoses typically require minimal treatment, but large ingestions may require gastrointestinal decontamination and intravenous fluids. A veterinarian should be contacted immediately if an overdose is suspected.

Cephalexin is widely prescribed because of its effectiveness, relatively low cost, and low incidence of serious side effects. It is not available over the counter and must be dispensed with a veterinary prescription. In some cases, cephalexin may be combined with other antibiotics to broaden antibacterial coverage. The medication often has a noticeable sulfur-like odor, sometimes compared to cat urine.

Dosage, frequency, and duration of treatment vary depending on the infection being treated, the pet’s response, and whether any adverse effects develop. Most pets show clinical improvement within 24 to 48 hours of starting therapy. If no improvement is observed, the veterinarian should be contacted. If nausea or vomiting occurs, administering the medication with food or a treat may help.

Drug and Laboratory Test Interactions

Cephalexin has relatively few drug interactions and is frequently given alongside medications for heart, respiratory, or thyroid conditions. However, potential interactions may occur with certain antibiotics such as aminoglycosides (including gentamicin), amphotericin B, chloramphenicol, cholestyramine, estrogens, furosemide, metformin, metoclopramide, omeprazole, pantoprazole, probenecid, and warfarin.

Veterinarians should be informed of all medications a pet is receiving to evaluate possible interactions. Cephalexin may also cause false-positive or altered results in certain laboratory tests, including glucose, albumin, Coombs tests, and urine protein measurements.

How Cephalexin Is Supplied and Stored

Cephalexin is most commonly available in 250 mg and 500 mg capsules and in tablets ranging from 50 mg to 1000 mg. Chewable scored tablets, such as Rilexine®, are available in 75 mg, 150 mg, 300 mg, and 600 mg strengths and are often flavored with liver and chicken to improve palatability.

Oral suspensions are available in strengths of 25 mg/mL, 50 mg/mL, 100 mg/mL, and 150 mg/mL, and most are stable for 14 days after reconstitution. An oral paste formulation at 100 mg/mL is also available. Tablets, capsules, and liquid formulations should be stored at room temperature between 65°F and 77°F. In some countries, injectable versions are available in concentrations of 150 mg/mL and 180 mg/mL.

Cephalexin Dosage for Dogs and Cats

Cephalexin is available only with a prescription from a licensed veterinarian and should never be administered without professional guidance. The typical dosage for dogs and cats ranges from 10 to 18 mg per pound (22 to 40 mg/kg) given orally every 6 to 12 hours for 7 to 28 days. In many cases, treatment continues for at least one week beyond resolution of clinical signs or until a negative culture test is obtained.

Chronic conditions such as pyoderma may require extended or maintenance therapy lasting several months to a year. A commonly prescribed dose is 10 to 15 mg per pound given twice daily. For example, a 10-pound dog or cat may receive approximately 100 to 150 mg per dose, while a 40-pound dog may receive 400 to 600 mg per dose. Reduced doses are recommended for pets with kidney disease.

Cephalexin should be administered at the same time each day. If a dose is missed and remembered within four hours, it should be given immediately, followed by the next dose at the regular scheduled time. If more than four hours have passed, the missed dose should be skipped and the regular schedule resumed. Double dosing should be avoided unless specifically directed by a veterinarian.

If gastrointestinal upset occurs, the medication may be given with food. The full course of treatment should always be completed unless otherwise directed, even if the pet appears to feel better, to reduce the risk of relapse or antibiotic resistance.

References