- current use of any medications known to interact with vasopressin including: 1) carbamazepine (i.e., Tegretol); chlorpropamide; clofibrate; urea; fludrocortisone; tricyclic antidepressants (all of which may potentiate the antidiuretic effect of vasopressin when used concurrently); 2) demeclocycline; norepinephrine; lithium; heparin; alcohol (all of which may decrease the antidiuretic effect of vasopressin when used concurrently); 3) ganglionic blocking agents including benzohexonium, chlorisondamine, pentamine (all of which may produce a marked increase in sensitivity to the pressor effects of vasopressin).