Use of ketoconazole to treat dogs with pituitary-dependent hyperadrenocorticism: 48 cases (1994-2007).

OBJECTIVE: To evaluate the effectiveness of ketoconazole as a treatment for dogs with pituitary-dependent hyperadrenocorticism (PDH).
DESIGN: Retrospective case series. ANIMALS: 48 client-owned dogs in which PDH was diagnosed. PROCEDURES: Medical records of dogs with PDH that were treated with ketoconazole were examined. Data collected from each record included signalment, clinical signs, results of ACTH stimulation tests before and after treatment with ketoconazole, serum alkaline phosphatase (ALP) and alanine aminotransferase (ALT) activities, dosage of ketoconazole, clinical response, and survival time.
RESULTS: 43 of 48 (90%) dogs had evidence of clinical improvement during the treatment period. In all dogs, treatment with ketoconazole resulted in significantly lower serum cortisol concentrations as measured before and after ACTH stimulation testing; 69% (33/48) of serum cortisol concentrations measured after ACTH stimulation were within the reference range. Serum ALP and ALT activities significantly decreased after treatment with ketoconazole. Survival time after diagnosis of PDH ranged from 2 to 61 months (mean, 26.9 months; median, 25 months). CONCLUSIONS AND CLINICAL RELEVANCE: Ketoconazole was a safe and effective option for treating dogs with PDH. Additional research is needed to evaluate the effects of long-term treatment with ketoconazole on adrenal glands.