Treatment of Canine Alopecia X with Trilostane

The study investigated the use of trilostane, a competitive inhibitor of 3β-hydroxysteroid dehydrogenase, in treating canine Alopecia X in 16 Pomeranians and 8 miniature poodles. The dogs exhibited clinical signs of Alopecia X, elevated 17-hydroxyprogesterone levels, and increased urinary cortisol/creatinine ratios. Trilostane was administered at an average dose of 10.85 mg/kg/day, either once or twice daily. Over a follow-up period of 28 months for Pomeranians and 33 months for miniature poodles, 85% of Pomeranians and all miniature poodles experienced complete hair regrowth within 4 to 8 weeks. No adverse effects were noted, suggesting that trilostane effectively promoted hair regrowth, potentially through the down-regulation of adrenal steroids or noncompetitive inhibition of estrogen receptors at the hair follicle level.