Veterinarian-Reviewed Top 5 Prescription Pituitary and Antidiuretic Therapies for Dogs in Canada (2026), DDAVP, Vetoryl, Lysodren, Anipryl, Percorten-V: What Your Vet Wants You to Know

DDAVP is the go-to ADH replacement for canine central diabetes insipidus because it provides a highly specific vasopressin analog in an easy-to-dose oral tablet, enabling reliable control of polyuria/polydipsia with minimal systemic steroid or adrenal effects. Compared with adrenal-directed therapies on this list (trilostane, mitotane, DOCP), DDAVP targets the neurohypophyseal axis directly and usually delivers lower monitoring intensity and lower ongoing lab costs, making it a cost-efficient chronic option for ADH-deficient patients.

Vetoryl is the market-leading trilostane capsule for canine hyperadrenocorticism because it reversibly inhibits steroidogenesis, allowing dose titration and predictable control of clinical signs without the adrenal destruction risk associated with mitotane. In practice Vetoryl often balances efficacy, safety and monitoring costs better than Lysodren for moderate-to-severe Cushing’s, and it is generally preferred over pituitary-directed drugs like selegiline when robust cortisol suppression is required.

Lysodren (mitotane) remains a best-in-class cytotoxic adrenal suppressant for dogs with severe Cushing’s because of its potent, sometimes durable adrenal-ablative effect and comparatively low per-unit drug cost. That potency gives it an economic advantage in acquisition cost, but it carries higher short-term monitoring and complication risks than trilostane and may produce higher downstream veterinary and hospitalization expenses when intensive induction protocols are required.

Anipryl (selegiline) is a selective monoamine oxidase B inhibitor used for pituitary-dependent disease modulation and cognitive dysfunction in dogs; it is valued for its oral convenience, favorable safety profile, and relatively low price for mild-to-moderate pituitary-driven signs. While less potent than trilostane or mitotane for controlling overt hypercortisolism, Anipryl can be an economically sensible first-line or adjunct therapy for early PDH or when neurobehavioral benefits are desired without aggressive adrenal suppression.