Metyrapone is used for the medical control of hypercortisolism in Cushing's syndrome (ACTH dependent or independent). The aim for medical treatment is to achieve pre-operative control of hypercortisolism, or for control of residual disease persisting post-operatively (TSS, adrenalectomy). It is not for long term definitive treatment/cure, only as an adjunct (surgery is the aim for cure in most causes of Cushing's syndrome). Metyrapone hence acts by inhibiting adrenal steroidogenesis. One side effect is hirsutism (in women) because of the excess androgen precursors created. The other commonly used agent for medical treatment of Cushing's is ketoconazole (an anti-fungal agent). This does not exhibit the side effect of hirsutism.
Desonate was approved by the FDA following two major clinical trials in 2006. Each randomized, double-blind, placebo-controlled study enrolled 582 pediatric patients (between the ages of 3 months and 18 years).  The patient was topically administered the drug or placebo two times a day for four weeks. Using the Investigator’s Global Severity Score (IGSS), the treatment was considered successful if at Week 4 there was at least a two (2) point decrease from the patient’s baseline IGSS. In clinical trial 1, 44% of patients succeeded successful treatment of Desonate versus 14% treated with the placebo. In clinical trial 2, 28% of patients succeeded successful treatment of Desonate versus 6% treated with the placebo.