Cephalexin for dogs is considered safe for dogs when used under veterinary supervision. The typical dosage ranges from 10 to 15 mg per pound (22 to 30 mg per kilogram) of body weight, administered every 8 to 12 hours, depending on the severity of the infection. It's effective against various bacterial infections, including those affecting the skin, urinary tract, bones, and respiratory system. While cephalexin is generally well-tolerated, possible side effects include vomiting, diarrhea, and lethargy. Always follow your veterinarian’s guidance on dosing and duration to ensure safety and effectiveness, and never stop the medication prematurely to prevent antibiotic resistance.