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VIP (Vasoactive Intestinal Peptide)28 residuesHSDAVFTDNYTRLRKQMAVKKYLNSILNEach bubble = one amino acid. Size = residue mass. Color = chemical class.Also known as: VIP, aviptadil, Vasoactive Intestinal Polypeptide
Twenty patients. That's the total from the only published VIP trial for CIRS, and every single one showed biomarker normalization. VIP (Vasoactive Intestinal Peptide) is a 28-amino-acid neuropeptide used intranasally as the final step in the Shoemaker protocol for Chronic Inflammatory Response Syndrome. No independent replication exists yet. The Shoemaker clinic reports over 10,000 patients treated since 2008, with consistent drops in TGF-beta 1, C4a, and MMP-9. CIRS patients who have completed all prior protocol steps use VIP to target brain fog, inflammatory marker normalization, and grey matter restoration.
Twenty-eight amino acids. A plasma half-life of roughly one minute. And a patient community that swears it gave them their brain back. VIP, or Vasoactive Intestinal Peptide (CAS 37221-79-7), is a neuropeptide produced throughout the gut, lungs, and central nervous system. It binds VPAC1 and VPAC2 receptors on immune cells, neurons, and smooth muscle tissue. In clinical practice, VIP has one primary context: step 12 of Dr. Ritchie Shoemaker's treatment protocol for CIRS (Chronic Inflammatory Response Syndrome) caused by mold and biotoxin exposure. Patients spray it intranasally at 200 to 400 mcg per day, bypassing the rapid plasma degradation that would destroy it in systemic circulation. Rat studies confirmed that roughly 0.1% of an intranasal dose reaches brain tissue through olfactory and trigeminal nerve pathways (Dufes et al.)[1]. Shoemaker's open-label trial of 20 patients (SCIRP, 2013) showed normalization of TGF-beta 1, C4a, MMP-9, and VEGF. His NeuroQuant MRI series reported grey matter volume restoration. The Shoemaker clinic cohort now exceeds 10,000 patients since 2008. Community reports from r/CIRS and biotoxinjourney.com consistently describe brain fog clearing within 2 to 4 weeks. The honest limitation: all CIRS-specific VIP data comes from Shoemaker's own publications, which are not PubMed-indexed and have not been independently replicated. CIRS itself lacks a formal ICD diagnosis code. Mainstream medicine remains skeptical. Aviptadil (synthetic VIP) does hold FDA orphan drug designation for pulmonary arterial hypertension, and COVID-19 ARDS trials were published in 2025.
VIP binds two G-protein-coupled receptors, VPAC1 and VPAC2, scattered across immune cells, neurons, smooth muscle, and epithelial tissue. Receptor activation triggers adenylyl cyclase, which raises intracellular cAMP. That cAMP increase sets off an anti-inflammatory cascade with several downstream effects. First, NF-kB activation gets suppressed. That means lower production of TNF-alpha, IL-6, and IL-12. Second, VIP shifts the T-helper balance away from Th1 and Th17 dominance toward regulatory T-cell expansion. Treg cells are the immune system's off switch for runaway inflammation; in CIRS, that switch is stuck. In blood vessels, VIP relaxes smooth muscle. It's a potent vasodilator, roughly 50 to 100 times more potent than acetylcholine on a molar basis (Domschke et al.)[2]. That vasodilation reduces pulmonary artery pressure, which matters for CIRS patients with exercise intolerance. In the brain, VIP protects neurons from oxidative damage and excitotoxicity. The intranasal route is what makes this possible. Sprayed into the nose, VIP reaches the CNS directly through olfactory and trigeminal nerve pathways. This bypasses the one-minute plasma half-life that would destroy it in systemic circulation. Dufes and colleagues confirmed this delivery pathway in rat models [1], showing about 0.1% of the intranasal dose reaching brain tissue, with a CNS Tmax of approximately 30 minutes.
Intranasal VIP normalizes CIRS inflammatory biomarkers (TGF-beta 1, C4a, MMP-9, VEGF) and restores grey matter volume in Shoemaker protocol patients. Evidence is exclusively from Shoemaker's own unindexed case series: no independent RCTs exist. Aviptadil (synthetic VIP) has FDA orphan drug designation for PAH; COVID-19 ARDS trials published 2025.
Shoemaker et al. 2013 (SCIRP, not PubMed-indexed): open-label 20-patient trial; RNA-Seq transcriptome study (ESMED 2022); NeuroQuant grey matter restoration series (Shoemaker 2017)
All CIRS-specific VIP trials are Shoemaker's own publications in SCIRP: not PubMed-indexed and not independently replicated. CIRS is not a recognized ICD diagnosis in mainstream medicine. The 15,071 PubMed VIP papers cover basic science and non-CIRS indications, not the Shoemaker protocol. Shoemaker clinic reports 10,000+ patients since 2008, but no independent registry or audit exists.
Highly valued as the final step of the Shoemaker CIRS protocol. Patients who have completed all prior steps consistently report brain fog resolution, biomarker normalization, improved energy, and quality of life recovery. Starting VIP before completing steps 1–10 (especially MARCoNS eradication) is the most common and costly error.
Within the CIRS framework, Shoemaker's clinical series and the patient community converge on the same protocol, dosing range (200–400 mcg/day), prerequisites, and expected biomarker outcomes. Mainstream medicine does not recognize CIRS as a formal diagnosis: this creates a broader disconnect with general scientific consensus, but that external disagreement does not affect the internal alignment between Shoemaker's data and patient community reports.
| Level | Dose / Injection | Frequency |
|---|---|---|
| Beginner | 200mcg | Daily |
| Moderate | 200mcg | 2x Daily |
| Aggressive | 400mcg | Daily |
Your first VIP vial comes as a nasal spray, not an injectable. Standard compounding: 5 mg vial reconstituted in 10 mL bacteriostatic water gives 500 mcg/mL. Each spray actuation delivers 0.1 mL, which equals 50 mcg per spray. Four sprays per dose means 200 mcg total. The biggest mistake people make is starting VIP too early. MARCoNS must be eradicated and confirmed negative on retest. VCS must be passing. If you skip those prerequisites, you'll spend $189 to $399 per month on a peptide that won't work because the underlying inflammation source is still active. Alternate nostrils with each spray (two sprays per nostril per dose). Morning dosing before food is standard. If you're sensitive, ask your prescriber about a 1:10 or 1:100 dilution for the first week; that dilution step makes initiation worsening much less likely. Get fasting lipase drawn before you start. No exceptions. Monthly lipase for three months after that.
In the Shoemaker protocol, VIP is often continued for 1-3 months until lab markers (TGF-beta, C4a, VEGF, MMP-9) normalize. Some patients use VIP intermittently for maintenance.
VIP treatment in CIRS continues until biomarkers normalize (TGF-beta 1, C4a, MMP-9, VEGF) and VCS improves: typically 8–12 weeks. Continuation beyond that is individually determined by biomarker response. Cycling is driven by safety monitoring checkpoints (lipase) and therapeutic endpoints rather than receptor desensitization. Intermittent maintenance use is common in patients with ongoing re-exposure risk.
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Expected: TGF-beta 1 <2,380 pg/mL, C4a <2,830 ng/mL, MMP-9 <332 ng/mL, VEGF 31–86 pg/mL. Passing VCS. Cognitive clarity and grey matter volume restoration on NeuroQuant MRI.
Monitor: Fasting lipase required before start (must be normal). Monthly lipase × 3 months, then quarterly. TGF-beta 1, C4a, MMP-9, VEGF at baseline and every 4–8 weeks. VCS testing monthly. Stop VIP immediately if lipase elevates.
Confirm prerequisites are met: MARCoNS eradicated (negative retest), VCS passing, fasting lipase normal (<60 U/L), and Shoemaker protocol steps 1 through 11 completed.
Obtain VIP nasal spray from a licensed 503A compounding pharmacy. Standard concentration: 5 mg vial in 10 mL bacteriostatic water = 500 mcg/mL. Each actuation delivers 0.1 mL = 50 mcg per spray.
Prime the spray bottle per pharmacy instructions before first use.
Alternate nostrils: 2 sprays in the left nostril, 2 sprays in the right. Tilt the head slightly forward.
If titrating to twice daily, add a second dose in the early afternoon.
Beginner schedule: 200 mcg once daily (4 sprays) for weeks 1 to 2. Moderate: 200 mcg twice daily (8 sprays total, 400 mcg/day) starting week 3 if tolerated. Aggressive: 400 mcg once daily (8 sprays) is the Shoemaker protocol maximum; do not exceed 400 mcg/day.
Sensitive patients: dilute VIP 1:10 or 1:100 during week 1 to reduce initiation worsening risk.
Storage: refrigerate at 2 to 8 degrees C (36 to 46 degrees F) at all times. Reconstituted vial is stable for 30 days. Discard if cloudy, discolored, or left at room temperature.
Monitoring: fasting lipase monthly for the first 3 months, then quarterly. TGF-beta 1, C4a, MMP-9, and VEGF every 4 to 8 weeks. VCS testing monthly.
IV aviptadil doses studied for PAH/ARDS are orders of magnitude different from intranasal CIRS dosing; clinical contexts not interchangeable.
Aviptadil is synthetic VIP. IV plasma half-life ~1 minute: even shorter effective exposure than intranasal CNS delivery via olfactory/trigeminal pathways. IV is not a viable or practiced CIRS route. Intranasal is the only route used in Shoemaker's published CIRS protocol.
Complementary T-cell and immune modulation. Some CIRS practitioners add TA1 for patients with concurrent immune deficiency or persistent infections. No clinical trial data on VIP + TA1 combination.
Adjunct NF-kB suppression for CIRS patients with prominent gut inflammation. KPV is occasionally added during earlier Shoemaker steps and may continue into the VIP phase. No formal protocol exists.
VIP is a potent vasodilator (50–100× more potent than acetylcholine on a molar basis). Additive hypotension risk: significant in CIRS patients who may already have orthostatic intolerance.
Both VIP and PDE5 inhibitors cause vasodilation via overlapping cGMP/cAMP pathways. Compounding hypotension risk.
Do not combineOverlapping immune modulation. May blunt or unpredictably alter VIP's immune-normalizing effects. Corticosteroids also suppress endogenous VIP signaling.
Pricing updated 2026-04-09
Lipase elevation is the safety signal that matters most. In Shoemaker's cohort of 600 patients with monitoring data, 4 developed raised lipase levels during VIP treatment, an incidence of roughly 0.7%. The protocol requires an immediate stop if lipase rises above normal (<60 U/L). This is a non-negotiable safety checkpoint, not a suggestion. Fasting lipase must be normal before starting, then checked monthly for three months, then quarterly. Transient initiation worsening affects approximately 10 to 15% of patients during the first week. Community reports describe it as dysphoria, a "toxic feeling," or palpitations. The Shoemaker clinic recommends diluting VIP 1:10 or 1:100 for sensitive patients during week one. These symptoms typically self-resolve within 3 to 7 days. Reducing concentration rather than stopping is the standard approach. Mild nasal irritation and congestion are common with intranasal delivery. Some patients report transient headache in the first two weeks. Both are expected and usually resolve without intervention. Diarrhea and nausea can occur but are uncommon at standard intranasal doses (200 to 400 mcg per day). These are more typical of intravenous VIP, where systemic exposure is much higher. Hypotension is a real risk, though rare at intranasal doses. VIP is 50 to 100 times more potent than acetylcholine as a vasodilator (Domschke et al.)[2]. Patients on antihypertensives or phosphodiesterase inhibitors (sildenafil, tadalafil) face additive risk. Blood pressure monitoring during initiation is reasonable for anyone with orthostatic intolerance. Contraindications are strict. VIP is contraindicated in pregnancy and breastfeeding. It should not be used in patients with VIP-secreting tumors (VIPomas), severe hypotension, or active MARCoNS infection. A failing VCS test means VIP should not be started, as it indicates unresolved biotoxin burden. Starting VIP before completing Shoemaker protocol steps 1 through 11 is the single most common and costly error the community reports. When to stop: immediately if lipase elevates. If no biomarker improvement appears after 12 weeks, the most likely cause is ongoing biotoxin re-exposure or incomplete prior treatment steps.
Verify VIP (Vasoactive Intestinal Peptide) dosing and safety with a second opinion
VIP must be obtained from a licensed 503A compounding pharmacy. Research-grade or "for research only" vendors do not meet pharmaceutical quality standards for human use. Rapid degradation at room temperature makes cold-chain integrity critical. No FDA-approved intranasal VIP formulation exists: no standardized quality benchmark outside of USP compounding standards.
| Test | When | Target |
|---|---|---|
| Fasting lipase | Required before starting (must be normal); monthly × 3 months; then quarterly | Must be normal (<60 U/L typical) before starting; stop VIP immediately if elevated during treatment |
| TGF-beta 1 | Baseline, then every 4–8 weeks | <2,380 pg/mL (Shoemaker normal range) |
| C4a (complement) | Baseline, then every 4–8 weeks | <2,830 ng/mL |
| MMP-9 (matrix metalloproteinase-9) | Baseline, then every 4–8 weeks | <332 ng/mL |
| VEGF (vascular endothelial growth factor) | Baseline, then every 4–8 weeks | 31–86 pg/mL |
| Visual Contrast Sensitivity (VCS) test | Must pass before starting VIP; monthly during treatment | — |
Lipase elevation in ~0.7% of patients (4/600 in Shoemaker cohort). P0 safety requirement of the Shoemaker protocol. Currently absent from peptides.ts sideEffects field.
Primary biomarker of CIRS severity and VIP treatment response. Elevated at baseline; should trend downward.
Key marker of innate immune dysregulation in CIRS. Should normalize with effective VIP treatment.
Surrogate marker for systemic inflammation in CIRS. Should decrease with effective VIP treatment.
Characteristically LOW in CIRS: VEGF deficiency contributes to exercise intolerance and poor tissue perfusion. VIP should restore levels to normal range.
Shoemaker protocol prerequisite: failing VCS means VIP should not be initiated. Improving VCS during treatment confirms response and absence of ongoing biotoxin re-exposure.
Initial intranasal dosing begins. Some patients notice mild nasal irritation. No significant clinical changes expected yet.
Early improvements in energy, mental clarity, and exercise tolerance. Inflammatory markers may begin to trend downward.
Measurable reductions in TGF-beta 1, C4a, and MMP-9 in responding patients. VEGF levels begin to normalize. Improved sleep and reduced brain fog.
Significant normalization of inflammatory markers in most responders. NeuroQuant MRI may show grey matter improvements. Many patients reach treatment goals.
Maintenance phase or tapering based on lab results. Retreatment may be needed if re-exposure occurs.
Days 1 through 7 (Initiation): VIP binds VPAC1 and VPAC2 receptors in nasal epithelium and reaches the CNS through olfactory and trigeminal pathways. Early cAMP upregulation begins. Most patients notice nothing perceptible. Around 10 to 15% report transient dysphoria, palpitations, or a "toxic feeling" that resolves within 3 to 7 days. Diluting to 1:10 or 1:100 concentration handles this for sensitive patients. Weeks 2 through 4 (Early Response): Inflammatory cytokine balance starts shifting. Treg expansion begins, and early reductions in TGF-beta 1 and C4a appear in responders. Brain fog lifting is the most commonly reported sign during this window. Energy picks up. Sleep quality improves. Mild nasal irritation may persist but is manageable. Weeks 4 through 8 (Biomarker Normalization): Lab work starts confirming what patients feel. Measurable drops in TGF-beta 1, C4a, and MMP-9. VEGF levels begin recovering. Shoemaker's RNA-Seq data from this window shows a shift toward an anti-inflammatory metabolic state. Community members run follow-up labs and post results showing markers trending into normal ranges. Exercise tolerance improves. Joint and muscle aches ease. Weeks 8 through 12 (Grey Matter and Full Response): Shoemaker's NeuroQuant MRI series documented grey matter nuclear volume restoration at this stage. Most biomarkers reach normal ranges in responders. Patients in the CIRS community describe this phase as "getting their brain back." Quality of life improvements become clear and sustained. Month 3 and beyond (Maintenance): Sustained normalization holds if biotoxin re-exposure is avoided. Most patients taper or stop after biomarkers normalize. Some continue intermittent dosing for maintenance if ongoing exposure risk exists. The strongest community consensus: VIP cannot prevent relapse from re-exposure to water-damaged buildings.
VIP binds VPAC1/VPAC2 receptors in nasal epithelium and reaches CNS via olfactory/trigeminal pathways. Early cAMP upregulation and NF-kB suppression begin. No measurable biomarker change expected this early.
Most patients report no perceptible change. Approximately 10–15% report transient dysphoria, "toxic feeling," or palpitations: the most discussed initiation experience in the CIRS community.
Progressive shift in inflammatory cytokine balance. Treg expansion begins. Early TGF-beta 1 and C4a reduction in responding patients.
Brain fog lifting is the most frequently reported early sign. Energy improvements. Sleep quality begins to improve.
Measurable reductions in TGF-beta 1, C4a, MMP-9. VEGF levels begin recovering. Shoemaker's RNA-Seq data shows shift toward anti-inflammatory metabolic state and innate immune normalization.
Patients run follow-up labs and report markers trending toward normal ranges. Improved exercise tolerance. Reduced joint and muscle aches. Clearer thinking.
Shoemaker NeuroQuant MRI series shows grey matter nuclear volume restoration in responding patients. Most biomarkers normalized by week 12 in responders.
Patients describe this as "getting their brain back." Significant quality of life improvement. Some continue VIP beyond 12 weeks for full grey matter restoration.
Sustained normalization if biotoxin re-exposure is avoided. Re-exposure causes rapid relapse: VIP cannot prevent re-exposure-driven CIRS recurrence.
Most patients taper or stop after biomarker normalization. Intermittent use for symptom management in patients with unavoidable exposure risk. Strongest community message: "Don't waste your money if you're still in a moldy building."
Source: Domschke et al. 1978: ~1 min plasma half-life via IV; intranasal delivery bypasses rapid plasma degradation via direct CNS uptake
Loading the interactive decay curve.
VIP (Vasoactive Intestinal Peptide) does not have FDA approval for intranasal use in CIRS. It is classified as research-only for this application. Aviptadil, the synthetic form of VIP, holds FDA orphan drug designation for pulmonary arterial hypertension and received Fast Track designation for that indication. No FDA-approved intranasal VIP product exists. Intranasal VIP for CIRS is compounded under 503A pharmacy regulations on a per-patient prescription basis. It requires a valid prescription from a licensed practitioner. Compounding pharmacies producing VIP must comply with USP <797> sterility standards. Athletes should note that VIP's regulatory status with WADA has not been explicitly addressed. Consult a sports medicine physician before use if subject to anti-doping testing. This content is for educational purposes only. It does not constitute medical advice, diagnosis, or treatment. Consult a qualified healthcare provider before using any peptide.
Peptide Schedule Research TeamReviewed Apr 20264 Citations
