What is VIP?

VIP is vasoactive intestinal peptide, a 28-amino-acid neuropeptide with vascular, pulmonary, immune, and nervous-system signaling roles. [1][2][3]

Drug-development discussions often use aviptadil for synthetic VIP. Research has explored pulmonary hypertension, inflammatory lung disease, sarcoidosis, and immune modulation. [1][2][3]

VIP is biologically broad, which makes it interesting but also easy to overclaim. Route, indication, and formulation drive the evidence interpretation. [1][2][3]

What VIP is investigated for

VIP evidence is grouped by practical use case and injectable and intranasal route context. Each use case separates confidence, human evidence, animal or mechanistic support, and the practical takeaway.

Pulmonary hypertension and vascular lung support

Injectable, Intranasal

53% Emerging

Pulmonary hypertension is the most concrete VIP lung indication discussed here, but it remains limited rather than approved. [1][3][4]

Human evidence

Inhaled VIP has been studied in pulmonary hypertension, and reviews discuss pulmonary arterial hypertension drug-development limits. [1][3][4]

Animal / mechanistic evidence

VIP vasoactive biology supports the pulmonary-vascular rationale, but trial translation remains difficult. [1][3][4]

COVID-19 and ARDS lung support

Injectable, Intranasal

42% Preliminary

COVID-19 and ARDS support should be separated from pulmonary hypertension and kept preliminary. [2]

Human evidence

Aviptadil/VIP has been discussed for COVID-19 lung injury, but the reviewed source is not enough to establish a standard treatment role. [2]

Animal / mechanistic evidence

The rationale is pulmonary epithelial and vasoactive support in acute lung injury. [2]

Autoimmune and inflammatory signaling

Injectable, Intranasal

38% Preliminary

Autoimmune and inflammation claims remain broad biology claims, not specific CIRS, gut, or neurodegenerative indications. [25][5]

Human evidence

Clinical translation for VIP-axis autoimmune and inflammatory disease use is not established in the cited literature. [25][5]

Animal / mechanistic evidence

VIP-axis reviews and animal-model literature support anti-inflammatory and immunoregulatory plausibility. [25][5]

Gut inflammation and motility

Injectable, Intranasal

28% Limited

Gut inflammation and motility are plausible VIP biology use cases, but they remain preclinical rather than established clinical indications. [9][10]

Human evidence

Human treatment outcomes for VIP in IBD, IBS, motility disorders, or gut-barrier repair are not established in the cited literature. [9]

Animal / mechanistic evidence

VIP physiology reviews and animal models support roles in intestinal inflammation and motility regulation. [10][12][9]

Neuroprotection in Alzheimer and Parkinson models

Injectable, Intranasal

26% Limited

Neuroprotection is a model-based VIP signal, not a proven Alzheimer or Parkinson treatment. [11]

Human evidence

Human neurodegenerative-disease outcomes for VIP treatment are not established in the cited literature. [11]

Animal / mechanistic evidence

Cell-model work supports VIP-related protection against beta-amyloid and Parkinson-relevant oxidative stress toxicity. [11]

Evidence snapshot

Overall confidence

Emerging

53%

VIP has limited-human support in vascular and pulmonary research plus broader immune-signaling plausibility. Broad anti-inflammatory or neurologic uses need narrow route and disease framing. [1][2][3]

Overall confidence is a page-level composite, not an average; it weighs evidence quality, route/molecule match, and practical limitations.

53%

Human evidence

Emerging

Human pulmonary studies exist, but they do not establish a broad VIP product or wellness indication. [1][2][3]

34%

Animal / preclinical

Limited

VIP receptor biology supports vasodilation, smooth-muscle relaxation, and pulmonary plausibility. [1][2][3]

53%

Mechanism support

Emerging

VIP binds VPAC receptors and can relax smooth muscle, dilate blood vessels, and modulate immune-cell signaling. The mechanism fits vascular and inflammatory signaling, not broad therapy confidence. [1][2][3]

Forms & administration

VIP appears in injectable and intranasal discussions, with pulmonary and immune research contexts. Route, blood-pressure context, and product format change the protocol meaning. [6][1][2]

InjectableNasal spray

Dosing & protocols

The notes below separate published trial design from commonly discussed cosmetic or compounded-use patterns. They are educational context only, not a prescription or product instruction.

Typical Range

Common injectable protocols usually use 50-100 mcg per dose; intranasal products need spray-specific interpretation. [6][1][2]

Frequency

Common schedules use 1-2 sessions daily, with route and blood-pressure tolerance kept visible in the log. [6][1][2]

Timing Considerations

Morning or evening timing is the common anchor; timing is otherwise route- and condition-specific. [6][1][2]

Cycle Length

Common VIP blocks run 3-6 months before comparing respiratory, inflammatory, blood-pressure, and tolerability notes. [6][1][2]

What to expect

Same day

Injectable or intranasal VIP may feel route-specific through breathing comfort, airway symptoms, sinus response, or vascular sensations. [1][2][3][6]

Weeks 2-8

Injectable or intranasal VIP blocks may show changes in respiratory symptoms, exercise tolerance, and inflammatory-symptom patterns. [1][2][3][6]

After stopping

Vascular or respiratory effects may soften after injectable or intranasal VIP exposure ends as underlying disease control becomes the main driver. [1][2][3][6]

Safety profile

VIP safety is route-aware and vascular: flushing, headache, dizziness, blood-pressure effects, pulmonary disease status, and product route all matter. [1][2][3]

Common side effects

Flushing [1][2][3]
Headache [1][2][3]
Dizziness [1][2][3]

Cautions

Low blood pressure [1][2][3]
Cardiovascular disease [1][2][3]
Pulmonary disease care [1][2][3]
Route identity [1][2][3]

What we don't know

Long-term repeated VIP use, disease-specific benefit-risk, intranasal absorption, and compounded-product quality remain uncertain. [1][2][3]

Who VIP is not for

Route-specific avoid and medical-review notes:

Severe hypotension
Severe hypotension warrants medical review or avoidance for VIP. [1][2][3]
Unstable cardiopulmonary disease without specialist review
Unstable cardiopulmonary disease without specialist review warrants medical review or avoidance for VIP. [1][2][3]
Pregnancy or breastfeeding
Pregnancy or breastfeeding warrants medical review or avoidance for VIP. [1][2][3]

Drug & supplement interactions

Documented interactions are separated from theoretical or route-specific cautions.

Theoretical interactions

Antihypertensives / nitrates / PDE5 drugs
Blood-pressure medicines, nitrates, or PDE5 inhibitors can compound flushing, dizziness, or hypotension; this is a route-specific vascular caution. [1][2][3]
Pulmonary vasodilators
Pulmonary hypertension therapies can add vascular effects and make blood-pressure response harder to interpret; this is a theoretical pathway caution. [1][2][3]
Other nasal sprays
Decongestant, steroid, or irritating nasal sprays can add local irritation or change intranasal exposure; this is a route-specific caution. [1][2][3]

Regulatory status

United States

In the U.S. as of 2026-06-21, VIP has no FDA-approved drug product for the reviewed injectable and intranasal routes. Research-market supply and compounded preparations are separate from approval; the 503A row names the current compounding bucket. [6][7][14][15]

Route	FDA drug approval	503A compounding
Injectable	Not Approved VIP is not FDA-approved as an injectable drug in the U.S. for the reviewed use; research-market supply and compounding are separate from FDA approval. [6][7][14][15]	Not Listed VIP is not in the current reviewed 503A compounding bucket for the injectable route; compounding status is separate from FDA drug approval. [6][7][14][15]
Intranasal	Not Approved VIP is not FDA-approved as an intranasal drug in the U.S. for the reviewed use; research-market supply and compounding are separate from FDA approval. [6][7][14][15]	Not Listed VIP is not in the current reviewed 503A compounding bucket for the intranasal route; compounding status is separate from FDA drug approval. [6][7][14][15]

Injectable

FDA drug approval

Not Approved

VIP is not FDA-approved as an injectable drug in the U.S. for the reviewed use; research-market supply and compounding are separate from FDA approval. [6][7][14][15]

503A compounding

Not Listed

VIP is not in the current reviewed 503A compounding bucket for the injectable route; compounding status is separate from FDA drug approval. [6][7][14][15]

Intranasal

FDA drug approval

Not Approved

VIP is not FDA-approved as an intranasal drug in the U.S. for the reviewed use; research-market supply and compounding are separate from FDA approval. [6][7][14][15]

503A compounding

Not Listed

VIP is not in the current reviewed 503A compounding bucket for the intranasal route; compounding status is separate from FDA drug approval. [6][7][14][15]

International

EU/Europe, UK, Canada, and Australia require product-specific checks in EMA/MHRA, Health Canada, and TGA registers. Research-market, supplement, or compounded availability should not be treated as therapeutic approval in those markets. [17][18][19][20]

Sports & competition

WADA S0 can apply to non-approved pharmacological substances that are not otherwise named. Tested athletes should not treat VIP injectable and intranasal routes as athlete-cleared without sport-specific review. [8][6][7][14][15]

How it works

VIP binds VPAC receptors and can relax smooth muscle, dilate blood vessels, and influence immune-cell signaling. In practical terms, it is a vasoactive and immunomodulatory peptide whose pathway connects pulmonary tone, inflammation, flushing, and blood-pressure effects. [1][2][3]

Route changes the risk story. Injectable or intranasal exposure can make cardiovascular symptoms, headache, heart rate, pulmonary disease status, and immune context more important, so broad immune, brain-health, or recovery claims should stay behind route-matched human outcomes. This keeps pathway breadth from becoming a generalized treatment claim. [1][2][3]

Research gaps & open questions

What the current literature has not yet settled about VIP:

A key evidence gap is condition-specific randomized trials. [1][2][3]

A key evidence gap is intranasal versus injectable pharmacokinetics. [1][2][3]

A key evidence gap is blood-pressure and cardiopulmonary safety in real-world users. [1][2][3]

Common questions

Is VIP FDA-approved?

No. VIP is not FDA-approved in the U.S. for injectable or intranasal drug use; aviptadil-style availability does not create U.S. approval. [6][7][1][2]

Is VIP anti-inflammatory?

Yes. VIP has anti-inflammatory and vasoactive signaling, but that pathway does not establish a broad injectable or intranasal immune-treatment protocol. [6][7][1][2]

Is VIP proven for MCAS or chronic inflammatory syndromes?

Not proven. Current evidence does not establish a general VIP protocol for MCAS or chronic inflammatory syndromes, and cardiovascular route risks still matter. [6][7][1][2]

Myths & misconceptions

Myth

Because VIP affects many systems, it helps many conditions.

Reality

Broad biology can also mean broader risk and less specific evidence. [1][2][3]

Myth

Vasodilation is always beneficial.

Reality

Blood-pressure and cardiovascular status can make vasodilation risky. [1][2][3]

History & discovery

VIP was identified as a vasoactive intestinal and neuroendocrine peptide before aviptadil-style development moved it toward pulmonary vascular and inflammatory disease research. That distinction keeps the origin story tied to evidence strength, route, and product identity rather than broad clinical certainty. [1][2][3]

Inhaled VIP and pulmonary-hypertension research connected the peptide to smooth-muscle relaxation and vascular tone. That route-specific history matters because blood-pressure effects are part of the mechanism. [1][2][3]

COVID-era aviptadil discussion broadened attention to anti-inflammatory and lung-protective pathways. The milestone widened interest but kept evidence tied to specific indications and routes. [1][2][3]

Published research 12 studies

[1]

Inhalation of vasoactive intestinal peptide in pulmonary hypertension.

Eur Respir J, 2008 Nov. review.

[2]

Anticipated pharmacological role of Aviptadil on COVID-19.

Environ Sci Pollut Res Int, 2022 Feb. review.

[3]

Pulmonary arterial hypertension: on the way to a manageable disease.

Curr Opin Investig Drugs, 2008 Sep. review.

[4]

Why drugs fail in clinical trials in pulmonary arterial hypertension, and strategies to succeed in the future.

Pharmacol Ther, 2016 Aug. review.

[5]

Investigation of vasoactive intestinal peptide expression and significance in a congenital diaphragmatic hernia animal model.

Pediatr Surg Int, 2025 Dec 4. animal.

[6]

Drugs@FDA/openFDA query for VIP

U.S. Food and Drug Administration. database query.

[7]

Compounding and the FDA: Questions and Answers

U.S. Food and Drug Administration. official guidance.

[8]

The 2026 List of Prohibited Substances and Methods

World Anti-Doping Agency. regulatory.

[9]

Recent advances in vasoactive intestinal peptide physiology and pathophysiology.

PubMed Central, 2019. review.

[10]

Therapeutic effects of vasoactive intestinal peptide in the trinitrobenzene sulfonic acid-induced colitis model.

PubMed, 2003. animal.

[11]

Vasoactive intestinal peptide (VIP) prevents neurotoxicity in neuronal cultures: relevance to neuroprotection in Parkinson's disease.

PubMed, 2000. in vitro.

[12]

Vasoactive Intestinal Polypeptide Plays a Key Role in the Microbial Regulation of Intestinal Motility.

PubMed, 2024. animal.