Research Information Only — Educational content, not medical advice or a prescription recommendation. VIP is not FDA-approved for wellness, CIRS, or long-COVID use. Physician review required before use of any compound discussed here.
Why This Page Exists
The peptide the market won't cover honestly
Search VIP and you'll find two things: clinics selling it as a mold-illness miracle, and forums full of people who tried it out of order and got worse. Almost nobody explains the one fact that decides whether VIP helps or fails — that it is the final step of a sequenced protocol, not a starting point. This profile grades the evidence honestly, states the regulatory reality plainly, and names exactly who VIP is — and isn't — for.
In one sentence
VIP tells overactive inflammatory cells to calm down and re-regulates a disordered immune response. Its strongest real-world use is the last stage of the Shoemaker CIRS protocol — after binders, sinus colonization, and hormones are already addressed. Used first or alone, it commonly fails.
Regulatory Status
Legal & regulatory context
United States — FDA
Orphan Drug (Aviptadil) · Not Approved for Wellness
The synthetic recombinant form, Aviptadil, holds FDA orphan-drug status for acute respiratory distress syndrome (ARDS) and pulmonary arterial hypertension, and was studied in COVID-19 respiratory-failure trials with mixed results. VIP is not FDA-approved for CIRS, mold illness, long COVID, optimization, or longevity. Those are investigational uses.
Research / Investigational
Compounded & Research-Grade
Outside its orphan indications, VIP reaches patients as a physician-compounded intranasal preparation or as a research chemical. Quality, potency, and delivery-device consistency vary widely (see Sourcing & Quality below).
WADA
Gray Zone for Athletes
VIP is not explicitly named on the current WADA Prohibited List, but as a peptide hormone with signaling activity it sits in an ambiguous zone. Competitive athletes should verify current WADA status independently before use.
Not a Controlled Substance
Prescription Reality
Genuine Aviptadil is prescription-only. VIP is not DEA-scheduled, but that does not make research-chemical sourcing safe or its clinical claims legal — vendors promising to "cure" CIRS or long COVID are violating FTC advertising rules.
Molecular Profile
Structure & identity
Class
Secretin/Glucagon Superfamily
28-amino-acid neuropeptide; first isolated by Said & Mutt in 1970 from intestinal tissue, later found throughout the nervous, pulmonary, gut, and immune systems.
Receptors
VPAC1 & VPAC2
Two G-protein-coupled receptors: VPAC1 drives immune and inflammation regulation; VPAC2 drives vasodilation and hormone signaling. The dual activity explains both the anti-inflammatory benefit and the blood-pressure caution.
Endogenous
Yes — Body-Made
Produced natively in central and peripheral nerves, gut, lung, and immune tissue. VIP is a physiological "resolve inflammation" signal, not a foreign molecule.
Primary Route
Intranasal
Intranasal delivery is preferred because it crosses the blood-brain barrier for central nervous-system access — central to both CIRS and neuroinflammation use. A subcutaneous form exists but is reserved for systemic immune work.
Mechanism of Action
Five ways VIP re-regulates inflammation
VIP works at the intersection of immune signaling, the brain, and the vasculature. Its defining action is telling the immune system's inflammatory arm to switch off and its regulatory arm to switch on.
01
Macrophage repolarization (M1 → M2)
The most-studied mechanism. VIP shifts macrophages from the inflammatory M1 phenotype toward the regulatory, tissue-repairing M2 phenotype, suppresses TNF-α, IL-6, IL-12, and IFN-γ, and expands regulatory T cells.
VIP → VPAC1 → ↓ TNF-α · IL-6 · IL-12 · IFN-γ → ↑ M2 macrophages · ↑ Tregs
02
Antigen-presentation (HLA-DR) re-regulation
Central to the Shoemaker CIRS model: VIP is hypothesized to help re-regulate disordered antigen presentation after mold-biotoxin exposure or post-infectious inflammatory syndromes — the step that lets a stuck immune response finally reset.
03
Vasodilation (VPAC2)
VIP is a potent vasodilator on vascular smooth muscle — the basis for the ARDS and pulmonary-hypertension research, and simultaneously the reason it can drop blood pressure in susceptible people.
VIP → VPAC2 → vascular smooth-muscle relaxation → ↓ pulmonary & systemic vascular resistance
04
Neuroprotection & microglial calming
Delivered intranasally, VIP crosses the blood-brain barrier, modulates microglial activation, reduces neuroinflammation, and supports neurogenesis in preclinical models (Delgado 2008; Gonzalez-Rey 2007) — the rationale for long-COVID and brain-fog applications.
05
Mast-cell stabilization
VIP reduces mast-cell degranulation, which is why it's discussed as an adjunct in mast cell activation syndrome (MCAS) — though the same population can flare early before stabilizing (see Cautions).
Primary Use Cases
What VIP is actually used for
- Chronic Inflammatory Response Syndrome (CIRS) / mold biotoxin illness Observational
The flagship use. The Shoemaker protocol established intranasal VIP as its final step; clinic observational data showed improvements in symptom severity, visual-contrast (VCS) testing, and inflammatory labs. Not FDA-validated for this indication.
- Neuroinflammation & post-viral cognitive issues (long COVID) Observational
Widely discussed for long COVID, post-acute infection syndromes, and persistent neuroinflammation. Intranasal delivery is preferred for direct CNS access.
- Mast cell activation syndrome (MCAS) support Anecdotal
Integrative-medicine and forum reports of reduced flare frequency, balanced against early-flare risk in a subset.
- Pulmonary applications (ARDS, pulmonary hypertension) Clinical data
Inhaled Aviptadil has genuine clinical-trial data here — this is the orphan-drug indication — though it is not the primary research-compound use case.
- Autoimmune adjunct Preclinical
Animal models show benefit in colitis, arthritis, and lupus models; not yet validated in clinical populations.
Who VIP is NOT for
Healthy optimization, weight loss, performance, or baseline longevity. The forum evidence is selection-biased toward severe, complex chronic illness — healthy people have no reason to use VIP, and it should not be marketed to them.
The Decisive Detail
VIP is the last step — not the first
This is the single most important thing to understand about VIP, and the reason most self-directed attempts fail. In the Shoemaker CIRS protocol, VIP is deployed only after the earlier stages are complete:
- Remove exposure — get out of the water-damaged environment first; nothing works while exposure continues.
- Binder therapy — cholestyramine or equivalent to clear circulating biotoxins.
- MARCoNS treatment — clear the multiply-antibiotic-resistant sinus colonization that keeps inflammation lit.
- Correct hormones & antigliadin antibodies — restore the axes the illness has disrupted.
- Only then: intranasal VIP — to re-regulate the immune response and lock in recovery.
Why order matters
Used as a standalone or first-line therapy — before binders and sinus colonization are handled — VIP is associated with incomplete response and protocol failure. The compound isn't failing; the sequence is. This is exactly the kind of decision logic vendors selling VIP will never tell you.
Evidence Summary
What the research actually shows
| Source / basis | Type | Key finding |
|---|
| Said & Mutt, 1970 | Discovery | First isolation of VIP from intestinal tissue; established it as an endogenous neuropeptide with vasoactive and signaling roles. |
| Delgado et al., 2008 · Gonzalez-Rey et al., 2007 | Preclinical | VIP modulates microglial activation, reduces neuroinflammation, and supports neurogenesis in animal models — mechanistic basis for CNS applications. |
| Shoemaker protocol literature | Observational | Intranasal VIP as final CIRS step; clinic-reported improvements in symptom scores, VCS testing, and markers (TGF-β1, C4a, MMP-9). Not FDA-validated. |
| Aviptadil ARDS trials (Relief Therapeutics / NeuroRx) | Phase 2/3 | Inhaled Aviptadil for COVID-19 respiratory failure — mixed results; did not yield full FDA approval for that indication. Orphan-drug status retained for ARDS/PAH. |
| Preclinical autoimmune models | Animal | Benefit shown in colitis, arthritis, and lupus models; not yet translated to controlled human trials. |
Relative evidence strength by application
Pulmonary (ARDS/PAH)
Moderate · Clinical
CIRS / mold illness
Observational
Long COVID / neuroinflammation
Early · Observational
Autoimmune adjunct
Preclinical
Honest evidence note
Outside its pulmonary orphan indications, VIP's human evidence is observational and comes from complex-illness populations. Mechanistic depth is strong; controlled clinical validation for CIRS and long COVID is not. Anyone claiming VIP is "proven" for those uses is overstating the record.
Protocols & Timeline
Dosing consensus
The dosing below reflects the published Shoemaker intranasal approach and integrative-medicine practice. It is not prescribing guidance — VIP protocols require physician oversight, and the compound is fragile and easy to under-deliver.
Intranasal — primary route50 mcg/spray · 1 spray each nostril · 4× daily (≈200 mcg/day)
The standard CIRS route. Many protocols begin once-daily for the first week to assess tolerance, then escalate to four times daily. Compounded into a metered nasal-spray bottle — device quality matters as much as the peptide.
Subcutaneous — reserved50–100 mcg daily · separate syringe always
Used only for systemic immune modulation, not the preferred route for CIRS or neurological indications. Never combined with another compound.
TimingDistributed across waking hours · not at bedtime
Four doses spread morning → evening. No fasting requirement. VIP can be alerting, so the final spray is placed several hours before sleep.
What the timeline typically looks like
- Days 1–7: initial symptom changes — sometimes a brief intensification (Herxheimer-like) before improvement.
- Weeks 2–4: inflammatory markers (TGF-β1, C4a, MMP-9 in Shoemaker testing) begin shifting.
- Months 1–3: the meaningful improvement window for CIRS responders.
- Months 3–6: full protocol completion; symptom durability assessed, then taper. There is no fixed on/off cycle — VIP runs continuously until resolution and lab normalization.
Red Flags & Cautions
Where VIP goes wrong
- Hypotension risk. VIP is a vasodilator — low baseline blood pressure, orthostatic hypotension, or POTS can worsen. Monitor and start low.
- Mast-cell flares. Some MCAS patients flare before they stabilize; pre-treatment with mast-cell stabilizers may be prudent.
- Herxheimer reactions. Early worsening is common in CIRS protocols — not automatically a reason to stop, but a reason to titrate slowly.
- Pregnancy / breastfeeding / trying to conceive. Suppressed — no safety data.
- Active malignancy. Suppressed — immunomodulation in oncology is complex and unpredictable.
- Pulmonary hypertension or significant cardiovascular disease. Provider supervision essential given the vasodilatory effect.
- Protocol prerequisites. Not a standalone for CIRS — skipping earlier steps risks incomplete response and outright failure.
Sourcing & Quality
Scam & quality warnings
Compounded vs. research-chemical
Genuine Aviptadil is orphan-drug, prescription-only. Research-chemical VIP varies significantly in quality — a certificate of analysis is essential.
The sprayer is half the product
Intranasal delivery quality matters as much as the peptide. Cheap metered sprayers routinely under-dose or deliver inconsistently.
Cold chain or don't bother
VIP is fragile and degrades quickly at room temperature once reconstituted. Vendors selling pre-mixed solution without cold-chain shipping should be avoided.
"Cure-all" claims = red flag
Promises to cure CIRS, long COVID, autism, or autoimmune disease violate FTC rules. VIP is investigational. Suspiciously low bulk pricing signals purity problems.
Common Questions
VIP questions answered
Is VIP FDA-approved?
The synthetic form, Aviptadil, holds FDA orphan-drug status for ARDS and pulmonary arterial hypertension and has been studied in COVID-19 respiratory-failure trials with mixed results. VIP is not FDA-approved for wellness, optimization, longevity, CIRS, mold illness, or long COVID — those uses are investigational.
Why is VIP the "last step" of the CIRS protocol?
Because it re-regulates the immune response, and that reset only holds once the drivers keeping inflammation lit — ongoing exposure, circulating biotoxins, MARCoNS sinus colonization, and disrupted hormones — are already handled. Deploying VIP before those steps is the most common reason people report it "didn't work."
Why do some people feel worse when they start VIP?
A brief initial intensification — a Herxheimer-like reaction — is common in the first days, and some MCAS patients flare before stabilizing. Slow titration and physician supervision are how this is managed. Worsening that doesn't settle warrants stopping and reassessing.
Can healthy people use VIP for optimization or longevity?
No meaningful case exists for it. VIP is a targeted tool for specific chronic inflammatory conditions. The real-world evidence comes almost entirely from complex-illness populations; there's no baseline-optimization rationale, and the vasodilatory and immune effects carry avoidable risk in healthy users.
What does VIP pair with?
Within a supervised protocol it's discussed alongside Thymosin Alpha-1 (immune modulation), BPC-157 (gut repair when relevant), and MOTS-c or SS-31 (mitochondrial support in long COVID). It should be used cautiously with other vasodilators or blood-pressure medication, and is not meaningfully stacked with GLP-1 or growth-hormone peptides.
Related Research
Immune & inflammatory hub
About the Author
SD
Dr. Scott DelBoccio, DMD
Founding Author · PeptideReport.ai
Dr. DelBoccio is a clinician with thirty years of practice and a focus on peptide pharmacology and regenerative medicine. PeptideReport.ai exists to be the clinician-authored, education-only resource peptide research deserved — every compound profile is an independent synthesis of the primary literature, evidence-graded, reviewed, and corrected in the open. No products are sold on this site.
Full Disclaimer
VIP (Vasoactive Intestinal Peptide, VIP-28; synthetic form Aviptadil) is not approved by the U.S. Food and Drug Administration for wellness, optimization, longevity, CIRS, mold illness, or long-COVID indications. Aviptadil holds orphan-drug status for ARDS and pulmonary arterial hypertension only. Information on this page is for educational and scientific purposes and does not constitute medical advice, diagnosis, or treatment. Protocols described are drawn from published literature and clinician practice; they are not prescribing guidance. Any use of VIP should occur under the supervision of a qualified physician who can evaluate your history, medications, and specific condition. PeptideReport.ai does not manufacture, sell, or endorse any peptide preparation. Content addresses adults 21 and older. Evidence and regulatory classifications continue to evolve.