Larazotide vs Vasoactive Intestinal Peptide (VIP)
A neutral, side-by-side comparison of two healing & recovery peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
Larazotide
Larazotide (AT-1001) is a synthetic octapeptide that acts as a tight junction regulator — it competitively blocks zonulin, the primary physiological driver of intestinal permeability ('leaky gut'). It is one of the few compounds studied in human clinical trials specifically for tight junction dysfunction, with Phase 2 data in celiac disease demonstrating reduced intestinal permeability and symptom improvement even in the presence of ongoing gluten exposure.
Full profileVasoactive Intestinal Peptide (VIP)
28-amino acid neuropeptide found throughout the CNS, gut, and immune system. Functions as a potent anti-inflammatory, vasodilator, and neurotrophic factor. Research applications include CIRS (Chronic Inflammatory Response Syndrome), pulmonary arterial hypertension, autoimmune conditions, and gut motility disorders. Intranasal administration is most studied for CIRS and neuroinflammatory conditions.
Full profile| Larazotide | Vasoactive Intestinal Peptide (VIP) | |
|---|---|---|
| Category | Healing & Recovery | Healing & Recovery |
| Also known as | Larazotide acetate, AT-1001, INN-202 | VIP, vasoactive intestinal polypeptide, PHM-27 |
| Evidence | FDA-approved | Investigational (in trials) |
| Dosing range | 0.25mg–1mg mg, 3x daily (before meals) | 25mcg–100mcg mcg, Daily intranasal or 1–2x weekly subcutaneous |
| Administration | Oral (capsule), Subcutaneous injection (research use) | Intranasal spray, Subcutaneous injection, Inhalation (nebulized) |
| Key side effects | Headache (most commonly reported adverse event in trials), Nausea (mild), Generally well-tolerated — adverse event rate similar to placebo in clinical trials | Facial flushing, Transient hypotension, Nasal irritation (intranasal route), Tachycardia |
| Cited sources | 3 references | 2 references |
Key differences
- Evidence level differs: Larazotide is fda-approved, while Vasoactive Intestinal Peptide (VIP) is investigational (in trials).
- Administration: Larazotide — Oral (capsule), Subcutaneous injection (research use); Vasoactive Intestinal Peptide (VIP) — Intranasal spray, Subcutaneous injection, Inhalation (nebulized).
- Dosing units differ: Larazotide is dosed in mg, Vasoactive Intestinal Peptide (VIP) in mcg — they operate at different scales.
- Frequency: Larazotide is typically 3x daily (before meals); Vasoactive Intestinal Peptide (VIP) is Daily intranasal or 1–2x weekly subcutaneous.
- Research depth: this profile cites 3 sources for Larazotide vs 2 for Vasoactive Intestinal Peptide (VIP).
How each works
Larazotide
Zonulin upregulation disrupts the tight junction proteins occludin and claudin, allowing paracellular passage of antigens, LPS, and inflammatory triggers into systemic circulation. Larazotide acts as a tight junction agonist by competitively displacing zonulin from its receptor and directly stabilizing tight junction complexes. The Phase 2b CeD trial (N=342) showed larazotide reduced the ratio of lactulose/mannitol (L/M ratio, standard intestinal permeability marker) and improved GI symptom scores versus placebo in actively-challenged celiac patients.
Vasoactive Intestinal Peptide (VIP)
VIP activates VPAC1 and VPAC2 receptors coupled to cAMP, suppressing pro-inflammatory cytokines while promoting Th2 regulatory immune responses and Treg differentiation. In the CIRS/biotoxin illness framework pioneered by Shoemaker, VIP intranasal formulation demonstrates normalization of inflammatory markers and improvement in TGF-β, MSH, and VIP deficiency seen in CIRS patients. Pulmonary vasodilation effects have been studied for PAH.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.