Close monitoring in the beginning and after any dose adjustment is essential. Discontinue trilostane and contact your veterinarian immediately if signs of intolerance are seen. Common side effects include mild lethargy, vomiting, diarrhea, and appetite reduction, especially in the beginning. Most reactions are minor and are reversed by decreasing the dose or discontinuing therapy, but serious or fatal Addisonian reactions are also possible. Side effects should be followed by electrolyte (sodium and potassium) and ACTH testing. Once symptoms resolve, the drug can be restarted at 50 percent dose reduction.
The pituitary gland is the “boss”, so to speak, of the endocrine system. Its main responsibility is for producing hormones which control the various other endocrine glands in the body. The growth of a tumor in either gland causes an over-production of corticosteroid hormones which, when released into the system, produce symptoms such as hair loss. (The over-use of steroid drugs can have the same effect.) Other symptoms (in both dogs and horses) can include sweating, weight loss (in spite of increased appetite), listlessness, increased intake of water, and anemia. However, the most recognizable symptom is hair loss.