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Cephalexin is one of several antibiotics (medicines that kill bacteria) used to treat a range of bacterial infections in people, dogs, and other animals. Like other antibiotics, it does not work against viral infections.

It belongs to the class of antibiotics known as a first-generation cephalosporin. The drug also goes by the name cefalexin. These are the generic names for a drug that is known by the brand names Keflex, Biocef, and Keftab. Cephalexin for dogs is an oral medication and can be given with or without food. Offering the drug with food, however, can reduce the risk of some of the more common side effects.

Tell your vet if your dog is taking any other kind of drug, including herbal and over-the-counter remedies, or has a medical issue that might rule out cephalexin treatment, including:

  • side effects from other drugs
  • digestive upset
  • kidney disease
  • allergies
  • pregnancy, nursing

The World Health Organization includes this drug on its List of Essential Medicines. It is effective against gram-positive and gram-negative bacteria, and it kills these bugs by disrupting the growth of the bacterial cell wall and causing it to rupture.

According to the U.S. Food & Drug Administration, Cephalexin is a semisynthetic cephalosporin antibiotic It is 7-(D-α-amino-α-phenylacetamido)-3-methyl-3-cephem-4-carboxylic acid, monohydrate.

What Dog Diseases Are Treated With Cephalexin?

Cephalexin is effective against several infections in dogs, including:

  • Urinary tract (UTI)
  • Skin and soft tissue, such as hotspots and pyoderma
  • Bone
  • Respiratory tract
  • Ear (otitis)

The drug is considered a broad-spectrum antibiotic, and is effective against several bacteria, including:

  • Staphylococcus aureus
  • Streptococcus pneumonia
  • Haemophilus influenza
  • E. coli
  • Streptococcus pyogenes
  • Klebsiella pneumonia
  • Proteus mirabilis

Side Effects of Cephalexin in Dogs

As in humans, antibiotic treatment with drugs like cephalexin are usually well-tolerated. This drug can interact with other medications, including the antibiotic penicillin and some blood thinners. Some side effects to look out for include:

  • Nausea
  • Diarrhea
  • Vomiting
  • Panting
  • Drooling
  • Hyperexcitability
  • Skin rashes

If you see any of these side effects, contact your veterinarian.

Cephalexin is available by prescription. All antibiotics should be administered with veterinary supervision, and you must follow your medical professional’s instructions to the letter. Never give your dog antibiotics that have been left over from a prescription for a person or another animal.
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