Progestins are steroid hormones that are typically prescribed to postpone heat cycles or alleviate false pregnancies in female dogs and treat benign prostatic hypertrophy in male dogs. They may also be used for some types of skin problems or to modify aggressive behavior. Megestrol acetate and medroxyprogesterone are the most commonly used progestins in dogs. Potential side effects include increased thirst and appetite, behavioral changes, mammary gland enlargement, and an increased likelihood of developing diabetes mellitus, acromegaly (a hormonal disease that causes enlargement of the head), Cushing’s disease, uterine infection (pyometra), reproductive disorders, and some types of cancer.
Cardiovascular risk factors include the alteration or diminishing of her glucose tolerance and hyperinsulinism (become resistant to insulin), a change in lipoproteins (carry cholesterol in blood) fraction which can cause cardiovascular disease and atherosclerosis (deposition of fatty substances onto inner walls of arteries causing blockage), increased triglyceride levels, hypertension (abnormally high blood pressure), changes in her myocardium (middle muscular layer of heart wall), and increased concentration levels of several different clotting factors. Cardiomyopathy (a typically chronic disorder of heart muscle that may involve hypertrophy and obstructive damage to the heart), myocardial infarction (localized death of the myocardium tissue usually leading to heart failure), heart attack, stroke, and cerebro-vascular accidents have all been causes in deaths where AAS abuse was implicated. Of course the liver, the body’s primary filtration system will come under attack as it has to accommodate the increased toxicity. Among the liver problems promoted are holestatic jaundice (failure of bile flow that causes yellowish pigmentation of skin, tissues, and body fluids), peliosis hepatis (blood-filled cysts develop on liver), hepatocellular hyperplasia (unusual increase of an epithelial parenchymatous cell called hepatocytes in the liver), and cancer. Secondary filters such as the kidneys and gallbladder also become more susceptible to disease.