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Vasopressin & Analogs in Variceal Bleeding — Dosing & Clinical Use
Vasopressin (ADH)
Mechanism: Potent splanchnic vasoconstrictor → reduces portal and collateral blood flow. Compared to placebo, vasopressin stopped bleeding in 52% vs 18% of patients, but rebleeding rates were as high as 45%.
| Parameter | Details |
|---|
| Route | Continuous IV infusion |
| Dose | 0.2–0.4 U/min, can be increased up to 0.8 U/min |
| Duration | 24 hours maximum |
| Mandatory adjunct | Nitroglycerin IV starting at 50 mcg/min (max 400 mcg/min), titrated to maintain SBP ~90 mmHg |
Nitroglycerin is mandatory alongside vasopressin to counteract coronary artery constriction, prevent cardiac events, and reduce intrahepatic/collateral resistance.
Serious adverse effects of vasopressin alone:
- Bowel ischemia
- Hypertension
- Myocardial ischemia
- Cardiac arrhythmia
- Cardiac failure
Because of these significant side effects, vasopressin is seldom used in modern practice — it is largely replaced by terlipressin (where available) or octreotide.
Terlipressin (Synthetic Vasopressin Analog — Preferred)
Longer-acting, safer profile than vasopressin, and the only vasoactive agent shown to reduce mortality at 2 and 6 weeks in acute variceal bleeding (34% relative risk reduction in overall mortality vs placebo).
| Phase | Dose | Frequency | Duration |
|---|
| Initial control | 2 mg IV bolus | Every 4 hours | First 48 hours |
| Maintenance | 1 mg IV bolus | Every 4 hours | Up to 5 days total |
Adverse effects: arrhythmias, angina, limb ischemia (~2–4% of patients).
Comparative Agents (for context)
| Agent | Dose | Duration |
|---|
| Octreotide (preferred in USA) | 50 mcg IV bolus → 50 mcg/hr infusion | 3–5 days |
| Somatostatin | 250 mcg IV bolus → 250–500 mcg/hr infusion | 5 days |
Meta-analysis shows octreotide is more effective than vasopressin in achieving hemostasis, with a far superior safety profile. Octreotide is the drug of choice in the United States; terlipressin is preferred in Europe and South Asia.
Key Clinical Points
- Start vasoactive therapy immediately upon suspicion of variceal bleeding — even before endoscopy, ideally in the ED.
- Combine vasoactive drugs with endoscopic variceal ligation (EVL) and antibiotic prophylaxis (reduces infection rate by >50%).
- Vasopressin must never be given without concomitant nitroglycerin due to cardiac risk.
- Vasoactive drugs are continued for 2–5 days post-endoscopy to reduce early rebleeding.
Sources:
- Mulholland and Greenfield's Surgery, 7e, Table 59.15 (AASLD 2016 Practice Guidance–adapted)
- Yamada's Textbook of Gastroenterology, 7e, Vasoactive drug therapy section
- Sleisenger and Fordtran's GI and Liver Disease, Medical Management of Acute Variceal Bleeding
Recent evidence note: A 2026 meta-analysis (PMID
41853888) comparing continuous vs bolus terlipressin infusion is available for those optimizing terlipressin delivery. A 2024 systematic review (PMID
39298544) characterizes the adverse event profile of terlipressin in cirrhosis.