Baytril is the brand name for enrofloxacin, a type of antibiotic known as a quinolone antibiotic. It is made by Bayer Animal Health. Unlike some other antibiotics, Baytril is approved for use in dogs by the Federal Drug Administration (FDA), according to "The Pill Book Guide to Medication for Your Dog and Cat." Baytril is thought to produce fewer side effects than penicillin-based antibiotics.
Digestive Side Effects
Baytril may cause nausea and vomiting in dogs. Because of the nausea, the dog's appetite will go down. This may also be accompanied by diarrhoea, which is a common side effect for any antibiotic in dogs. According to Bayer Animal Health, vomiting usually occurs because the dog has been given too large a dose. Contact a vet if your dog vomits.
Neurological Side Effects
Baytril may cause dizziness or coordination problems in dogs, according to Bayer Animal Health. If the dog has seizures, contact a vet immediately. "The Pill Book Guide to Medication for Your Dog and Cat" notes that dogs that already have a disease or problem with their central nervous system will be more prone to dizziness or seizures than other kinds of dogs. Because of this tendency, Bayer Animal Health recommends that Baytril not be given to dogs with seizure problems like epilepsy or encephalitis ("water on the brain").
Urinary Side Effects
Baytril may cause crystals to form in urine. The crystals are made up entirely of enrofloxacin. Crystals could make bladder stones and block the urinary tract, making urine painful to pass. Dr. Brooks notes that this is a very rare side effect. Signs of crystals in the urine include dizziness, coordination problems, extreme thirst and an inability of the skin to bounce back into place when pulled. This is because dogs that are getting urine crystals become dehydrated, according to "The Pill Book Guide to Medication for Your Dog and Cat."
Developmental Side Effects
This type of side effect only occurs in puppies under eight months old. Baytril can interfere with the joint cartilage. As the puppies grow, the joint cartilage doesn't. Bayer Animal Health notes that although the puppy's joint cartilage is growing, the Baytril may erode it away. For this reason, puppies should never be given Baytril.