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Pet Health Articles

Dogs + Medications & Supplements

  • Levothyroxine is thyroid hormone replacement given by mouth in the form of a tablet or capsule. It is used to treat hypothyroidism and its use in cats and certain exotic animals is off label. This medication should not be used in pets with certain heart conditions, untreated Addison's disease, or hyperthyroidism.

  • Lincomycin is given by mouth or injection and is used on and off label to treat certain bacterial infections. Give as directed by your veterinarian. Common side effects include vomiting, diarrhea, or drooling. Do not use in pets that are allergic to it or similar drugs, in pets with a candida fungal infection, very young pets, or in rabbits, hamsters, guinea pigs, or horses. If a negative reaction occurs, please call the veterinary office.

  • Lokivetmab is given by injection and is used on and off label to treat itchiness in dogs. Give as directed. Side effects are uncommon but may include vomiting, diarrhea, sleepiness, lack of appetite, or pain at the injection site. Do not use in pets that are allergic to it. If a negative reaction occurs, please call the veterinary office.

  • Lomustine is given by mouth and is used off label to treat certain cancers such as mast cell tumors and brain tumors. Give this medication as directed by your veterinarian. Common side effects include vomiting, diarrhea, lack of appetite, and hair loss. Do not use in pets that are severely allergic to it. If a negative reaction occurs, please call your veterinary office.

  • Loperamide is given by mouth and is used off label to treat signs of diarrhea. Give as directed by your veterinarian. Common side effects include constipation, bloat, and sleepiness. Do not use in pets that are allergic to it, that have diarrhea due to an infection or a toxin, or that are positive for the MDR1 gene. If a negative reaction occurs, please call your veterinary office.

  • Lorazepam (brand names Ativan®, Lorazepam Intensol®) is a benzodiazepine medication used off label to treat behavior problems such as anxiety, fears, and phobias in cats and dogs. It can also be used to treat seizures or to stimulate appetite in cats. It is given by mouth or injection. Do not use in pets that are allergic to it or other benzodiazepines, or that have severe breathing problems, or liver disease. If a negative reaction occurs, please call your veterinary office.

  • Lotilaner is used to treat and prevent flea infestations and treat and control tick infestations in dogs and cats. After being administered to a pet, lotilaner is distributed throughout the body. When fleas or ticks bite the dog or cat, they are exposed to the drug and killed during their blood meal.

  • Lufenuron is a medication that controls flea infestations in dogs, cats, rabbits, and ferrets. It is given by mouth in the form of a tablet or liquid to dogs, cats, rabbits, and ferrets. It may also be given by injection to cats. Side effects are uncommon but may include vomiting, diarrhea, lack of appetite, tiredness, reddening of the skin, or itchiness. Do not use in pets that are allergic to it. If a negative reaction occurs, please call your veterinary office.

  • Marbofloxacin is given by mouth and is used on and off label to treat certain bacterial infections including leishmaniasis, tuberculosis, and hemoplasmosis. Common side effects include vomiting, diarrhea, and lack of appetite. Do not use in pets that are allergic to it or other quinolones, or in small and medium breed dogs before 8 months of age, in large breed dogs before 12 months of age, in giant breed dogs before 18 months of age, or in cats before 12 months of age. If a negative reaction occurs, please call your veterinary office.

  • Maropitant citrate (brand name Cerenia®) is given by mouth in the form of a tablet or injected under the skin and used to treat nausea and vomiting in dogs and cats. Common side effects include vomiting and increased salivation, or pain at the injection site. It is contraindicated in pets with a GI obstruction, GI toxicity, or in pets under 8 weeks old. Use caution in pets with heart or liver disease, or in pets under 16 weeks old.