Vasopressin

General

  • Type: Vasopressors
  • Dosage Forms:
  • Common Trade Names: Vasostrict (USA)

Adult Dosing

Dosing

  • 0.01-0.04 units/min (typically 0.03 or 0.04 U/min)

Rate of Titration

  • Fixed dose (do not titrate)

Pediatric Dosing

0.0002–0.008 U/kg/min have been studied although no current consensus on dosage [1]

Special Populations

  • Pregnancy Rating: C
  • Lactation:
  • Renal Dosing
    • Adult
    • Pediatric
  • Hepatic Dosing
    • Adult
    • Pediatric

Contraindications

  • Allergy to class/drug

Adverse Reactions

  • Bradycardia
  • Limb ischemia
  • Myocardial ischemia
  • Splanchnic ischemia

Pharmacology

  • Half-life: <20 minutes [2]
  • Metabolism: liver, kidney extensively; CYP450: unknown
  • Excretion: urine (5-6% unchanged)
  • Mechanism of Action: "directly stimulates V1 and V2 receptors, resulting in vasoconstriction and antidiuresis" [3]

Primary Receptor

  • V1

Relative Effects

  • ↑SVR
  • ↓HR

Notes

  • Adverse effects are dose-dependent
  • Acts on V1 receptors leading to ↑vasoconstriction and
  • ↑sensitivity to catecholamines in patients with shock
  • in contrast to catecholamine vasopressors (e.g. epinephrine, norepinephrine), vasopressin does not lose efficacy at low pH

Indication

  • Adjunct for septic shock VASST trial [4]
    • no difference in mortality when vasopressin was added as second line pressor compared to norepinephrine
    • subgroup analysis found that patients with less severe septic shock did better with vasopressin

See Also

References