Cephalexin is a cephalosporin antibiotic that treats different types of bacterial infections in cats and dogs, including skin infections, urinary tract infections (UTIs), and ear infections. It’s commercially available as tablets, capsules, and liquid, and is often prescribed off-label for pets to help them fight infections. You’ll usually give it to your pet by mouth twice a day. The most common side effects are diarrhea, vomiting, and reduced appetite.
Skin infections
Urinary tract infections (UTIs)
Bone infections
Abscesses
Infected wounds
Cephalexin is a cephalosporin antibiotic. It kills bacteria by preventing them from forming their protective outer walls around their cells, which they need to survive.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
First choice treatment for some skin infections in pets
Available as tablets, capsules, and a liquid
Can be given with food
Might need to be given multiple times a day
Doesn’t work for viral infections
Can cause diarrhea, vomiting, or reduced appetite
Cephalexin can be given with or without food, but it’s best to give it with food to prevent an upset stomach.
If you’re allergic to penicillin or cephalosporin antibiotics, handle cephalexin carefully since touching it could cause a reaction. If needed, someone without an allergy can give the medication to your pet or you can wear gloves for extra protection.
Even if your pet starts to feel better, it’s important to give the entire course of cephalexin as prescribed. Stopping the medication too soon can lead to antimicrobial resistance and might cause the infection to become even harder to treat.
Cephalexin hasn’t been well studied in pregnant or nursing dogs and cats. If your pet is pregnant or lactating, talk with your veterinarian to weigh the risks and benefits before giving this medication.
Store the liquid form of cephalexin in the refrigerator. Make sure to throw it away 14 days after you open it.
Cephalexin can cause some serious health issues. This risk might be even higher for certain pets. If this worries you, talk to your veterinarian about other options.
Risk factors: Allergy to penicillin antibiotics | Allergy to other cephalosporin antibiotics
If your pet is allergic to penicillin, there’s a chance they could also react to Cephalexin. The risk is also higher if your pet has had a reaction to other cephalosporin antibiotics. Talk to your vet right away if you notice signs of an allergic reaction, like a rash, fever, hives, or trouble breathing.
The dose will depend on your pet’s weight and the type of infection they have. Here are a few examples of typical dosing:
Dogs:
Skin infections and urinary tract infections (UTIs): The typical dose is 15 mg/kg to 30 mg/kg by mouth every 12 hours. In many cases, vets start closer to 22 mg/kg to 30 mg/kg, depending on your dog’s health and how they respond to the medication.
Cats:
Skin infections and urinary tract infections (UTIs): The typical dose is 15 mg/kg to 30 mg/kg by mouth every 12 hours. In many cases, vets start closer to 22 mg/kg to 30 mg/kg, depending on your cat’s health and how they respond to the medication.
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