Desmopressin (DDAVP, Stimate, Minirin)

Uremic platelet dysfunction - 0.3 mcg/kg IV over 30 min before invasive procedures restores platelet function within 30–60 min and lasts 6–12 hr.

Mild hemophilia A and von Willebrand disease (vWD) type 1 - Same 0.3 mcg/kg IV dose; only effective in patients with documented response to a test dose. Ineffective in severe hemophilia A and contraindicated in vWD type 2B (worsens thrombocytopenia) or type 3.

Central diabetes insipidus in OR/ICU - 0.3–1 mcg IV or subcutaneous; titrate to urine output and serum sodium.

Cardiac surgery bleeding adjunct - Limited but supportive evidence post-cardiopulmonary bypass when platelet dysfunction is suspected; 0.3 mcg/kg IV.

Strict free-water restriction after dose - Pair every hemostatic dose with a 24-hr fluid-restriction order and a sodium check at 12 and 24 hr; severe hyponatremia and seizures have been reported, especially in pediatric enuresis use.

Tachyphylaxis - Repeat dosing within 24–48 hr produces less response; plan a single perioperative dose.

Management of excessive effect - Restrict free water, give 3% saline if symptomatic hyponatremia, hold further doses; effect resolves over 6–24 hr.

Drug Interactions - Additive hyponatremia with selective serotonin reuptake inhibitors (SSRIs), carbamazepine, and nonsteroidal anti-inflammatory drugs (NSAIDs); reduced effect with demeclocycline and lithium.

Pediatric Implications - Used for nocturnal enuresis (oral) and for vWD/mild hemophilia A pre-procedure (IV 0.3 mcg/kg). Hyponatremic seizures and deaths have occurred when fluids were not restricted; do not use in children under 6 months.

Obstetric Implications - Considered safe in pregnancy and is preferred over factor concentrates for mild vWD and hemophilia A carriers when responsive. Compatible with breastfeeding because of negligible oral bioavailability in the infant. V1 (uterotonic) activity is minimal at clinical doses.

Absolute: moderate to severe renal impairment (creatinine clearance less than 50 mL/min), baseline hyponatremia, von Willebrand disease type 2B (causes thrombocytopenia), psychogenic polydipsia.

Relative: history of thromboembolism, severe coronary artery disease (factor VIII / vWF surge), severe heart failure, conditions predisposing to fluid overload.

Caution: pediatric enuresis (rigid fluid restriction required), elderly with multiple comorbidities, cystic fibrosis, concurrent SSRI or NSAID use.

Hemostatic indications (vWD type 1, mild hemophilia A, uremic platelet dysfunction): 0.3 mcg/kg IV in 50 mL normal saline (NS) over 30 min, maximum 20 mcg.

Central diabetes insipidus: 1–4 mcg IV every 12–24 hr, titrate to urine output and serum sodium.

Subcutaneous 0.3 mcg/kg for hemostatic indication when IV access is unavailable.

Selective V2-receptor agonist that increases water reabsorption at the renal collecting duct and triggers release of stored von Willebrand factor and factor VIII from vascular endothelium (Weibel-Palade bodies). Minimal V1 (vasopressor and uterotonic) activity at clinical doses.

Hepatic and renal (limited); largely excreted unchanged.

Renal.

Concentrations: IV/SQ 4 mcg/mL; intranasal Stimate 1.5 mg/mL (high-dose, hemostatic); intranasal DDAVP 0.1 mg/mL (low-dose, antidiuretic); oral 0.1 and 0.2 mg.

Refrigerate the IV vial; do not freeze.

Always dilute the IV dose in 50 mL NS and infuse over 15–30 min to reduce hypotension and flushing.

Document a 24-hr free-water restriction order and check sodium pre-dose and at 12 and 24 hr after a hemostatic dose.

Test-dose any patient with mild hemophilia A or vWD before relying on desmopressin for surgery; non-responders need factor concentrate.