Vasopressin (Arginine Vasopressin): veterinary dose and monograph

At a glance

Drug class

Cardiovascular

Also known as

AVP, ADH, Pitressin, Argipressin

Species with doses

Dogs and Cats

Routes

IV

Last reviewed

1 October 2026

Indications

• Cardiopulmonary resuscitation — vasopressor (alternative/adjunct to adrenaline)
• Catecholamine-refractory vasodilatory / septic shock (with norepinephrine)
• Vasoplegia unresponsive to adrenergic pressors (e.g. severe acidosis)

Vasopressin (Arginine Vasopressin) dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

• CPR (cardiac arrest): UNITS/kg. Papich 5e: 0.8 U/kg IV bolus, repeatable during CPR. Plumb’s p.1161 (Scroggin & Quandt 2009): 0.2–0.8 U/kg IV once for PEA or asystole, alternating with adrenaline 0.01 mg/kg.
• Catecholamine-refractory vasodilatory shock (CRI): Papich 5e: 0.01–0.04 U/min (0.5–5 mU/kg/min); do not exceed 0.04 U/min. Plumb’s p.1161: 0.01–0.04 U/min IV regardless of weight when fluids and catecholamines fail; risk of myocardial ischaemia; do not use in cardiogenic shock.

Cats

• CPR (cardiac arrest): UNITS/kg. Plumb’s p.1161: 0.2–0.8 U/kg IV once for PEA or asystole. Papich 5e (dogs and cats): 0.8 U/kg IV, repeatable.
• Catecholamine-refractory vasodilatory shock (CRI): Papich 5e (dogs and cats): 0.01–0.04 U/min (0.5–5 mU/kg/min). Plumb’s p.1161: 0.01–0.04 U/min IV. Diagnostic use after a water-deprivation test: 0.5 U/kg IM (Peterson & Randolph).

Contraindications

Uncorrected hypovolaemia (resuscitate volume first). Significant coronary/vascular disease (intense vasoconstriction → ischaemia). Extravasation risk. Known hypersensitivity. Reserve high-dose vasopressor use for arrest/refractory shock.

Adverse effects

• Intense vasoconstriction → myocardial/peripheral/splanchnic ischaemia at high doses
• Reduced cardiac output; bradycardia
• Tissue necrosis if extravasated
• Water retention/hyponatraemia (antidiuretic effect, with prolonged use)

Drug interactions

• Catecholamines (norepinephrine/adrenaline): complementary/additive vasopressor effect (different mechanism)
• Ganglionic blockers: enhanced pressor effect
• Drugs causing SIADH/fluid retention: additive antidiuretic effect

Pregnancy and lactation

Reserve for arrest/life-threatening shock; can affect uterine tone. Limited data.

Monitoring

• Blood pressure/perfusion and ECG (titrate; avoid over-vasoconstriction/gut ischaemia)
• Serum sodium with prolonged infusion (antidiuretic effect)
• IV catheter site (extravasation); response during CPR/shock

Toxicity and overdose

Excessive vasoconstriction causes myocardial, peripheral and SPLANCHNIC (gut) ischaemia, reduced cardiac output and, with prolonged infusion, water retention/hyponatraemia. Extravasation causes necrosis. The intense, non-selective vasoconstriction warrants careful titration and monitoring.

Management: Reduce/stop the infusion (short-acting). Manage ischaemic complications supportively; monitor for hyponatraemia with prolonged use. For extravasation, local phentolamine/nitroglycerin has been used. Continuous BP/ECG and perfusion monitoring.

Clinical pearls

• The NON-adrenergic pressor — works via V1 receptors independently of catecholamines, so it shines when adrenergic pressors fail (severe acidosis, catecholamine-refractory vasodilatory shock) and as an adjunct/alternative in CPR
• Dosed in IU; a CPR bolus during arrest, or a low-dose CRI added to norepinephrine in refractory shock
• Watch for splanchnic (gut) and peripheral ischaemia from intense vasoconstriction — titrate carefully; correct hypovolaemia first
• This is its vasopressor role — for diabetes insipidus, use desmopressin (V2-selective) instead

Mechanism of action

Stimulates V1a receptors on vascular smooth muscle (via phospholipase-C/IP3, RAISING intracellular calcium) to cause potent vasoconstriction and increased systemic vascular resistance — a mechanism entirely INDEPENDENT of adrenergic receptors, so it remains effective when catecholamine receptors are down-regulated or unresponsive (acidosis, refractory shock). At V2 receptors in the kidney it is antidiuretic (its physiological ADH role, exploited separately for diabetes insipidus via desmopressin).

Formulations and products

• Injection 20 IU/mL (dilute; IV or intraosseous)
• Pitressin / Argipressin — 20 IU/mL injection, Injection (dilute) (human-label)

Storage

Injection: REFRIGERATE per label, protect from light; dilute for infusion and use promptly.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

Other cardiovascular drugs

• Sildenafil
• Sodium Nitroprusside
• Sotalol
• Telmisartan

Frequently asked questions