Absorption
T max is about 2 to 8 h.

Metabolism
Majority of dose is metabolized and rapidly destroyed in the liver and kidneys.

Elimination
T ½ is about 10 to 20 min. About 5% of the dose is excreted unchanged in the urine after 4 h.

Alcohol, demeclocycline, heparin, lithium, norepinephrine
May decrease the antidiuretic effect of vasopressin.

Carbamazepine, chlorpropamide, clofibrate, fludrocortisone, tricyclic antidepressants, urea
May potentiate antidiuretic effect of vasopressin.

Ganglionic blocking agents
May markedly increase sensitivity to vasopressin pressor effects.