Vasopressin: Pitressin/Vasostrict water-retention & blood-pressure hormone
The body's own hormone that tells the kidneys to hold water and raises blood pressure; synthetic versions are FDA-approved hospital drugs used in diabetes insipidus and shock.
- Class
- Posterior pituitary neurohormone (V1a / V1b / V2 receptor agonist)
- Status
- FDA-approved prescription drug (Pitressin, Vasostrict and generics); hospital and ICU-restricted use
- Best-supported effect
- Antidiuretic replacement in central diabetes insipidus (human label) and catecholamine-sparing pressor support in vasodilatory/septic shock (human RCT and guideline-supported)
- Main caveat
- Mortality benefit in septic shock has not been demonstrated in landmark RCTs; nonselective V1a activity makes use outside continuous hemodynamic monitoring unsafe
A researcher, an agent, or an algorithm wrote down the sequence and picked a target to hit.
An AI model like OpenFold3 or AlphaFold built a 3D structure and scored how well it fits the binding site.
A second contributor repeated the computation on their own hardware and the scores matched.
A chemistry service or a researcher ordered the sequence, it was manufactured, and mass spectrometry confirmed the right molecule was produced.
A binding or activity measurement confirmed that it actually does what the computer predicted — or didn't.
What this is
Arginine vasopressin (AVP), also called antidiuretic hormone (ADH), is the body's own nine-amino-acid hormone for holding onto water and backing up blood pressure. It is made in the hypothalamus and released by the posterior pituitary gland whenever blood becomes too concentrated or blood pressure drops. Synthetic vasopressin is FDA-approved under the brand names Pitressin and Vasostrict (and generic equivalents) for central diabetes insipidus and postoperative abdominal distension, and is widely used in intensive care units as a catecholamine-sparing pressor in vasodilatory and septic shock. In practical terms this is a hospital and ICU drug, not a wellness or self-administered peptide.
The stored sequence CYFQNCPRG is the nine-residue backbone, but the active molecule is cyclic — an intramolecular disulfide bond locks Cys1 to Cys6, and the C-terminus carries an amide group (Gly-NH₂) rather than a free carboxylic acid; neither the ring closure nor the amide cap is visible in the raw sequence.
History
The story of vasopressin begins in 1895, when George Oliver and Edward Schäfer showed that posterior pituitary extracts raised blood pressure in dogs — the first pharmacological evidence for what would later be named vasopressin. By the 1910s Henry Dale had characterized the antidiuretic and uterotonic activities of the same extracts, and by the 1920s crude preparations sold as Pitressin and Pituitrin were in clinical use for diabetes insipidus, postpartum hemorrhage, and shock.
Structural determination and total synthesis were accomplished by Vincent du Vigneaud and colleagues at Cornell Medical College in the early 1950s, building on their 1953 synthesis of oxytocin — the first laboratory synthesis of a polypeptide hormone. Du Vigneaud's group identified vasopressin as a cyclic nonapeptide differing from oxytocin at only two positions (Phe at position 3 vs Ile; Arg at position 8 vs Leu), and was awarded the 1955 Nobel Prize in Chemistry for this work (du Vigneaud, Journal of Neurosurgery 2015).
Ferring Pharmaceuticals developed desmopressin in the 1960s by deaminating position 1 and substituting D-arginine at position 8, virtually eliminating V1a pressor activity while preserving V2 antidiuretic activity — the analogue now used for ambulatory diabetes insipidus and bedwetting. Terlipressin, a V1-selective prodrug, was developed in Europe in the 1970s–1980s and received FDA approval as Terlivaz for hepatorenal syndrome in 2022.
The modern critical-care role of native vasopressin took shape in the late 1990s and early 2000s. Landry and colleagues (NEJM 2001) articulated the relative-vasopressin-deficiency hypothesis: endogenous AVP stores are mobilized early in septic shock by baroreflex activation but become depleted after hours to days of sustained shock, removing a physiologic backstop against vasodilation. This hypothesis underpinned the VASST trial (Russell and colleagues, NEJM 2008) and the VANISH trial (Gordon and colleagues, JAMA 2016).
What it does
In the kidney, vasopressin tells collecting-duct cells to insert aquaporin-2 water channels into their membranes, causing the body to reabsorb water and produce a smaller, more concentrated urine — the antidiuretic effect that is absent in central diabetes insipidus (Sands and colleagues 2009). At the blood vessel level it causes direct constriction of vascular smooth muscle, raising blood pressure. In the anterior pituitary it triggers ACTH release as part of the stress axis.
In the ICU, a low-dose continuous infusion is added to norepinephrine when that catecholamine alone is insufficient to maintain blood pressure in vasodilatory or septic shock. Because vasopressin acts through its own V1a receptor pathway — distinct from adrenergic receptors — it continues to work even when adrenergic receptors have become desensitized from prolonged catecholamine exposure, making it a catecholamine-sparing adjunct rather than a replacement pressor.
Plasma half-life of circulating native AVP is approximately 10–20 minutes, which is why continuous infusion is used in shock rather than intermittent dosing, and why ambulatory diabetes insipidus management uses the longer-acting V2-selective analogue desmopressin rather than native vasopressin.
Evidence
- Human: Extensive. FDA label establishes antidiuretic replacement in central diabetes insipidus. The VASST trial (Russell and colleagues, NEJM 2008) — a Phase III RCT in adults with septic shock — did not show overall 28-day mortality benefit for vasopressin versus norepinephrine but demonstrated a possible signal in patients with less-severe shock. The VANISH trial (Gordon and colleagues, JAMA 2016) tested early vasopressin initiation versus norepinephrine in septic shock and likewise did not show a mortality benefit. An individual-patient-data meta-analysis across septic-shock RCTs found no effect on 28-day mortality but a reduction in renal replacement therapy requirement; confidence intervals remain wide. A systematic review and meta-analysis supports vasopressin use in post-cardiopulmonary-bypass vasoplegic shock. Meta-analytic evidence for vasopressin in cardiac arrest does not support routine inclusion, and most current advanced cardiac life support algorithms have removed it in favour of epinephrine alone. Copeptin — a stable byproduct of the AVP precursor, measured as a clinical surrogate for endogenous AVP — has been validated in RCTs as a diagnostic tool for AVP deficiency (Morgenthaler and colleagues 2007).
- Animal: Comprehensive. V1a, V1b, and V2 receptor pharmacology, osmoregulation, and baroreflex interactions have been characterized across multiple species.
- In vitro: Strong. V1a (Gq/PLC/IP3/DAG), V1b (Gq), and V2 (Gs/cAMP/PKA) signaling pathways are well-mapped in cell systems.
Myths and misconceptions
- "Vasopressin and desmopressin are basically the same drug." They differ in a clinically important way. Native vasopressin activates V1a receptors (vasoconstriction) at doses comparable to its V2 antidiuretic activity, which is why it is confined to the ICU. Desmopressin was engineered to eliminate V1a pressor activity while preserving V2 antidiuresis — that engineering is what makes it safe for chronic ambulatory use in bedwetting and diabetes insipidus. The two are not interchangeable.
- "Vasopressin is a first-line vasopressor for septic shock." Current Surviving Sepsis Campaign guidance positions norepinephrine as first-line and vasopressin as an add-on when MAP remains inadequate despite escalating norepinephrine doses. Neither the VASST nor the VANISH trial showed a mortality benefit for vasopressin as a standalone or early strategy; its role is adjunctive and catecholamine-sparing.
- "Vasopressin should be used instead of epinephrine in cardiac arrest because it lasts longer." Meta-analyses and a Cochrane review found no consistent benefit of vasopressin over or combined with epinephrine for return of spontaneous circulation, survival to discharge, or neurological outcome in cardiac arrest. Most current resuscitation algorithms have removed vasopressin as a routine option.
- "The two words 'diabetes' mean vasopressin helps diabetes mellitus." The shared word is a historical naming artifact (both conditions involve polyuria). Diabetes insipidus is a disorder of water handling caused by AVP deficiency or AVP resistance; diabetes mellitus is a disorder of glucose handling caused by insulin deficiency or resistance. Vasopressin has no role in diabetes mellitus management.
- "Copeptin is a new hormone that replaces vasopressin." Copeptin is not a separate hormone — it is a stable C-terminal glycopeptide cleaved from the same pre-pro-AVP precursor in equimolar amounts to vasopressin. It has largely replaced direct AVP measurement in endocrine workups because AVP itself is unstable in plasma; copeptin is a surrogate, not a replacement therapy (Morgenthaler and colleagues 2007).
Known effects
- Antidiuresis / water reabsorption — FDA-approved (central diabetes insipidus; V2 mechanism)
- Vasoconstriction / pressor support — Guideline-supported (vasodilatory and septic shock as adjunct to norepinephrine; V1a mechanism)
- ACTH release / stress-axis activation — Mechanistic (V1b receptor on anterior pituitary corticotrophs; well-characterized in humans and animals)
- Catecholamine-sparing in vasoplegic shock — Phase III RCT and meta-analysis (VASST; post-cardiopulmonary-bypass meta-analysis)
- Reduction in renal replacement therapy in septic shock — Meta-analytic signal; not a primary RCT mortality endpoint
- Cardiac arrest resuscitation — Not established; meta-analyses found no consistent benefit over epinephrine
Safety signals
Safety information below reflects published labels and clinical trial data; it is not personal medical advice.
| Signal | Evidence context | Notes |
|---|---|---|
| Skin blanching and pallor | Label / human use | V1a-mediated peripheral vasoconstriction |
| Digital ischemia | Label / human use | Risk rises above 0.03 U/min and in patients with peripheral vascular disease or Raynaud's phenomenon |
| Mesenteric ischemia and abdominal cramps | Label / human use | V1a-mediated splanchnic vasoconstriction; higher infusion rates increase risk |
| Coronary vasoconstriction | Label / human use | Can precipitate ischemia in patients with coronary artery disease |
| Bradycardia | Label / human use | Reported at therapeutic pressor doses |
| Hyponatremia | Label / human use | With prolonged or higher-dose antidiuretic exposure; worsens pre-existing SIADH |
| Infusion-site reactions and extravasation necrosis | Label / human use | Central venous administration is strongly preferred over peripheral line |
| Long-term neurocognitive and social outcomes after ICU exposure | Research gap | Animal V1a central-effect literature (social behavior, aggression) has not translated into well-characterized human outcomes after ICU vasopressin exposure |
Label-described contraindications include known hypersensitivity to vasopressin or formulation excipients (including chlorobutanol), chronic nephritis with nitrogen retention, coronary artery disease with unstable angina or recent myocardial infarction, severe peripheral vascular disease or Raynaud's phenomenon, documented mesenteric vascular disease, hyponatremia or history of SIADH, and pregnancy except where clearly indicated and alternatives are unavailable (uterine contraction via oxytocin-receptor cross-reactivity).
Regulatory status
- US (FDA): Prescription-only. Approved as Pitressin, Vasostrict, and generics for central diabetes insipidus and postoperative abdominal distension. Widely used off-label and consistent with professional guidelines (Surviving Sepsis Campaign) for vasodilatory and septic shock. Not a controlled substance. Dispensed to hospitals and healthcare institutions, not retail pharmacies.
- International: Approved across major markets for similar indications.
- WADA: Native vasopressin is not specifically named on the WADA Prohibited List. Its V2-mediated antidiuretic activity is potentially relevant to the S5 Diuretics and Masking Agents category; the V2-selective analogue desmopressin is explicitly prohibited. Athletes with a legitimate therapeutic need would require a Therapeutic Use Exemption.
The V1-selective analogue terlipressin (Terlivaz) received FDA approval in September 2022 for hepatorenal syndrome type 1 on the basis of the CONFIRM trial. The V2-selective analogue desmopressin has its own separate regulatory history and profile; both are distinct molecules and not used as evidence for native vasopressin's regulatory status here.
Mechanism
Vasopressin acts through three G-protein-coupled receptors:
- V1a (Gq / PLC / IP₃ / DAG) on vascular smooth muscle mediates vasoconstriction — the pressor effect exploited in critical care — and contributes to platelet aggregation and hepatic glycogenolysis.
- V2 (Gs / cAMP / PKA) on the basolateral membrane of renal collecting-duct principal cells drives aquaporin-2 trafficking to the apical membrane, increasing water reabsorption and concentrating urine. This is the principal antidiuretic mechanism described by Sands and colleagues (2009).
- V1b / V3 (Gq) on anterior pituitary corticotrophs drives ACTH release as part of the stress axis, particularly under sustained or chronic stress.
Endogenous release is governed by two stimuli: plasma osmolality, detected by hypothalamic osmoreceptors (the dominant driver under normal conditions), and effective circulating volume or arterial pressure, detected by cardiopulmonary and arterial baroreceptors (a higher-threshold but more powerful stimulus). Approximately a 1% rise in plasma osmolality produces measurable AVP release; a blood pressure drop of more than 10–20% produces high-amplitude release reaching pressor concentrations.
The therapeutic rationale for low-dose vasopressin in late septic shock rests on the relative-vasopressin-deficiency hypothesis: endogenous AVP stores are mobilized early by baroreflex activation but become depleted after hours to days of sustained shock, removing a physiologic backstop against vasodilation (Landry and colleagues, NEJM 2001). Vasopressin's V1a-Gq pathway is non-catecholamine and is not subject to adrenergic receptor desensitization, which is the pharmacologic basis for its use as a catecholamine-sparing adjunct rather than a stand-alone pressor.
Structurally, vasopressin and oxytocin are nine-amino-acid cyclic peptides differing only at positions 3 (Phe in vasopressin, Ile in oxytocin) and 8 (Arg vs Leu), which accounts for their cross-reactivity at each other's receptors — including vasopressin's potential uterotonic activity via oxytocin-receptor cross-reactivity in pregnancy.
Open questions
- Optimal timing of vasopressin initiation in septic shock. Whether to add vasopressin at low norepinephrine doses (early) or reserve it for refractory shock (late) is not resolved by current trial evidence; the VANISH trial's early-initiation strategy did not show mortality benefit.
- Vasopressin responder subgroups. The VASST signal for benefit in less-severe shock and the meta-analytic reduction in renal replacement therapy requirement suggest heterogeneity of treatment effect that is not yet characterised by clinical or biomarker features.
- Dose ceiling in refractory shock. Whether modestly higher infusion rates are safe and beneficial in refractory shock remains controversial; most guidance caps rates to limit ischemic risk.
- Copeptin as a real-time shock biomarker. Established as a diagnostic surrogate for AVP deficiency, copeptin's utility to guide vasopressin dosing or predict response in shock patients is only beginning to be studied.
- Positioning of V1a-selective analogues. Terlipressin has an established hepatorenal syndrome role, but its positioning versus native vasopressin in septic shock is still being defined.
- Long-term neurocognitive outcomes after ICU exposure. The animal V1a literature on social behavior and aggression has not translated into well-characterized human outcomes after ICU vasopressin use.
- Pediatric septic shock. Most RCT evidence is in adults; optimal indication selection and outcomes in pediatric septic shock are less well defined.
Related peptides
- Oxytocin (/card/pep-04424) — the closest structural relative; a nine-amino-acid cyclic neurohypophysial peptide differing from vasopressin at only two positions (Ile³, Leu⁸). Best known for uterine contraction and milk ejection; shares cross-reactivity at vasopressin receptors.
- Desmopressin (1-deamino-8-D-arginine vasopressin) — V2-selective synthetic analogue engineered to eliminate the V1a pressor activity of native vasopressin. Used for ambulatory central diabetes insipidus, primary nocturnal enuresis, and hemostatic indications.
- Terlipressin (triglycyl-lysine vasopressin) — V1-selective prodrug approved for hepatorenal syndrome type 1 (FDA, 2022) and used in Europe for variceal bleeding. Separate regulatory and clinical profile from native vasopressin.
Research directions for this peptide, selected from the current sources — hypotheses you can explore and model. None of it is proven yet; tap any one to see the full thinking.
If a patient in septic shock already has a struggling adrenal gland, could vasopressin help the pituitary squeeze out just enough cortisol to stabilize them?
If this holds, doctors might be able to identify a specific group of sepsis patients, those with partial adrenal failure but intact pituitary signaling, who get a double benefit from vasopressin: blood pressure support and a cortisol boost. That could mean fewer patients needing high-dose steroids and the side effects that come with them.
Could swapping the small chemical cap on vasopressin's end be enough to steer it toward the kidneys instead of the blood vessels?
If removing or altering this cap selectively weakens vasopressin's grip on one receptor type but not another, chemists could use it as a tuning knob to design cleaner, more targeted drugs. That would be a new tool for making safer vasopressin-based medicines beyond the handful of modifications already known.
Is there a version of vasopressin that keeps the kidneys safe but leaves blood flow to the liver alone?
Full-strength vasopressin is often avoided in critically ill patients whose livers are already under stress, because it tightens blood vessels feeding the gut and liver. If a modified version could skip that harm while still protecting the kidneys, it could reach a group of sepsis patients who currently have no good vasopressor option.
Could a patient's individual receptor makeup predict whether vasopressin will safely stop bleeding from ruptured veins in the liver without causing too much harm elsewhere?
Variceal bleeding in cirrhosis is life-threatening and hard to control. If a measurable receptor ratio in the blood vessels could flag which patients will respond well to vasopressin, doctors could use the drug more confidently in liver disease instead of avoiding it across the board. That could mean faster bleeding control and fewer patients excluded from an effective treatment.
Can vasopressin keep kidneys working in sepsis at doses too small to affect blood pressure?
Kidney failure requiring dialysis is one of the most devastating complications of sepsis. If vasopressin can protect kidney tissue through a separate mechanism that kicks in before any blood pressure effect, it could be given earlier and more broadly, and might spare patients the risk of dialysis without the blood vessel side effects that come with higher doses.
Are some of vasopressin's effects in critically ill patients actually coming from a receptor meant for oxytocin?
Vasopressin and oxytocin are close chemical cousins, and their receptors overlap. If high ICU doses of vasopressin are also triggering the oxytocin receptor, some of the variable heart responses seen across patients might finally have an explanation. That insight could lead to better dosing strategies that account for both receptors rather than treating vasopressin as a simpler agent than it actually is.
Could a modified vasopressin given by injection once a day replace the unreliable nasal spray for patients with damaged nasal tissue?
Diabetes insipidus causes constant extreme thirst and urination because the kidneys cannot hold onto water. The main treatment, desmopressin nasal spray, stops working reliably after nasal surgery or radiation. If a long-acting injectable version kept the same water-retaining action all day from a single dose, it would give patients with damaged nasal passages a stable, predictable alternative.
▸full evidence table2 metrics
| metric | value | tool |
|---|---|---|
| ipTM | 0.983540952205658 | boltz-2 |
| ranking score | 0.8598759770393372 | boltz-2 |
▸3-letter notation
▸recipeboltz-2 2.2.1
| parameter | value |
|---|---|
| model | boltz-2 2.2.1 |
| weights | — |
| hardware | vast_v100_32gb |
| mlx version | — |
| python | — |
| random seed | 1 |
| msa strategy | colabfold_local |
| runtime | — |
| predicted by | — |
| predicted at | 2026-05-22 |
▸citationbibtex
@peptide{pep04423,
sequence = {CYFQNCPRG},
target = {avpr1a},
author = {peptidemodel},
year = {2026},
status = {bioassayed}
}