Most dogs with HAC, Dr. Chapman said, are otherwise healthy. After testing the patient, the veterinarian needs to decide whether the benefits of treatment justify the risks for the patient and the expense for the owner. “The decision to treat should always be made based on the impact of the pet's clinical signs on the quality of life of dog and owner,” he advised.
Surgical options (eg, adrenalectomy for adrenal tumors) are available, but Dr. Chapman noted that dogs with HAC usually have a high risk of complica­tions when undergoing surgery and that it’s extremely important to make an accurate diagnosis prior to determining the optimal treatment plan.

Medical treatment is, by far, the most common approach to controlling HAC. Dr. Chapman discussed the two drug options, Trilostane and mitotane, noting some of their risks and benefits. Trilostane is a revers­ible inhibitor of cortisol production given at a twice-daily dose of 1 to 2 mg/kg; it is less effective when given once daily, he said, because of its 6- to 12-hour duration of effect. Mitotane, which is cytotoxic to adrenal cortex cells but spares zona glomerulosa cells responsible for mineralocorticoid production, is initiated at a daily dose of 50 mg/kg and then main­tained at a weekly dose of 50 mg/kg. It may be a good option for dogs that don’t respond to Trilostane. The primary complications associated with these drugs are hypocortisolemia (Trilostane) and hypoadrenocor­ticism (mitotane).

“No clear benefit of one medication over the other has been demonstrated for dogs with pituitary-dependent HAC,” Dr. Chapman said. He explained that prolonged median survival times (>2 years) have been reported with both medications, with most patients succumb­ing to problems other than the primary disease.

How to get Trilostane raw material (API)?

We know China is the biggest manufacturer of Trilostane powder in the world right now.  that's easy to get it from web.