Megace Side Effects in Dogs

Megace, also sold as "Ovaban," with the generic name megistrol, was developed for use in humans as part of a breast cancer treatment program. It reproduces effects similar to the hormone "progesterone" which encourages contractions and the development of breast tissue. It's also used in dogs to treat reproductive problems. While the drug is considered safe for use in animals, it can cause some side effects if used improperly.

  1. Dosages

    • Megace is made available for pets in 5, 20 and 40mg tablets to be taken orally. Different dosages are prescribed depending on the use and the size of the dog. When used to control heat cycles or treat false pregnancy, veterinarians prescribe a dose of .25mg per pound, once daily for up to eight days. For example, a dog weighing 10 lbs. receives a dosage of 2.5mg or half of a 5mg tablet daily.

    Warnings

    • Megace does cause side effects in animals, even though it is considered safe and effective. Do not give Megace to pregnant dogs or dogs with known allergies or hypersensitivity to the drug. Avoid giving it to animals with uterine disease, diabetes or breast cancer. Megace also interacts with other medications, such as antibiotics and steroids. Repeated use of Megace to control estrus in dogs increases the risk of developing future reproductive problems. like uterine infections.

    Symptoms

    • The adrenal gland is severely affected by the use of Megace and insufficiency of the adrenal gland can develop after being on the drug for a few weeks. Pets with adrenal problems will develop Addison-like symptoms, such as fatigue, muscle weakness, pain in the hind quarters, vomiting and diarrhea. Some vomiting and diarrhea can also occur without the other symptoms or adrenal problems. If the symptoms are severe or don't go away, consult with the veterinarian.

    Overdose

    • Don't give Megace to your dog without a veterinarian's prescription and precise dosages from the vet. If you suspect an overdose, contact your veterinarian immediately. A high overdose can have a strong impact on the adrenal glands. If you miss giving a dose to your dog, give that dosage as soon as you remember. If you remember about the missing dosage and it's close to time to give the next dosage, simply skip the missed dosage and give the dog the next dosage. Don't double up dosages to cover the missed dose.