Hyperadrenocorticism is characterized by chronically elevated circulating concentrations of the steroid hormones produced by the adrenal cortex and is a common endocrine disorder in dogs.1,2 Current treatments for dogs with PDH include a group of clinically evaluated drugs, only some of which effectively control the disorder.3–22 Two medications that are commonly used to treat dogs with PDH are mitotane (o,p'-DDD [1,1-dichloro-2-(2-chlorophenyl)-2-(4-chlorophenyl) ethane]) and trilostane.3–16 Ketoconazole, cyproheptadine, aminoglutethimide, and L-deprenyl are used for treatment, but studies17–22 in which the effectiveness of these drugs has been evaluated are limited and incomplete.
The imidazole derivative ketoconazole is often used as an antifungal agent in dogs.1,2,17,19 Ketoconazole also inhibits synthesis of steroid hormones by the gonads and adrenal glands by interfering with the activities of cytochrome P-450–dependent enzymes in the adrenal cortex.2,17,23,24 Among the drugs used to treat dogs with hyperadrenocorticism, ketoconazole is the only one legally available for veterinary use in Taiwan. The purpose of the study reported here was to evaluate the effects of ketoconazole in the treatment of dogs with PDH.
Cortrosyn, Organon, Oss, The Netherlands.
Coat-A-Count Cortisol, Diagnostic Products Corp, Los Angeles, Calif.
Nizoral, Janssen Pharmaceutica, Beerse, Belgium.
SPSS, version 13.0, SSPS Inc, Chicago, Ill.
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