VIP
Vasoactive intestinal peptide — 28 amino acids
A 28-amino-acid neuropeptide with broad effects on immune regulation, blood flow and gut function. Human trials exist but are small, and clinical use sits within a specific protocol rather than general practice.
- Category
- Immune & Gut
- Half-life
- Very short — approximately one to two minutes in circulation
- Cycle length
- Not standardised; the described clinical protocol involves several weeks of monitored use
- Level
- advanced
Overview
Vasoactive intestinal peptide is a neurotransmitter and hormone found throughout the nervous system, gut and immune tissues. It relaxes smooth muscle and dilates blood vessels, regulates secretion in the gut, and — unusually for a peptide — exerts a strong anti-inflammatory and immune-tolerancing effect. It appears in this library mainly because of one clinical context: it has been used in a named protocol for chronic inflammatory response syndrome, where low measured levels are treated with intranasal peptide. Outside that setting, human data is limited to small trials, and it is not an approved medicine.
How it works
VIP acts through VPAC1 and VPAC2 receptors on smooth muscle and immune cells, raising intracellular cyclic AMP. That signalling dilates vessels, relaxes gut and airway smooth muscle, increases secretion and shifts immune cells toward a regulatory, anti-inflammatory state, including effects on T-cell differentiation and on the balance of pro- and anti-inflammatory cytokines.
Reported benefits
- Potent anti-inflammatory and immune-modulating activity in laboratory and animal studies
- Vasodilation and improved blood flow in specific tissues
- Regulation of gut motility and secretion
- Evaluated as an inhaled therapy in a small trial of sarcoidosis
Reported benefits describe what the published literature and user reports suggest — not a promise of outcome for any individual.
Dosing reference
There is no approved dose. An inhaled formulation was studied in a small sarcoidosis trial, and intranasal use has been described within a specific clinical protocol for chronic inflammatory response syndrome, with dosing adjusted to measured levels under a practitioner's supervision.
Because VIP is cleared within minutes, delivery route determines almost everything about its effect. The dosing described in clinical protocols is titrated to lab markers and symptoms by a supervising clinician, which is not reproducible from a supplier's suggested schedule.
Community-reported: 25–100 mcg intranasally or by injection, once daily or in short courses, with reactions reported more often at the higher end.
These figures are what people report using in public communities. They have not been studied, verified or checked against certificates of analysis, and they are not a recommendation, a prescription or a target to aim for.
Where the reported amounts come from
Amounts are reproduced for education only. Doses from trials cannot be assumed to suit anyone else, and community-reported amounts are frequently wrong. Self-administering unapproved compounds carries serious risk.
The research picture
Human evidence for VIP is limited. A small randomised trial of inhaled VIP in pulmonary sarcoidosis reported improvement in some measures of immune activation and lung function, and case series describe intranasal use in chronic inflammatory response syndrome with reported symptom and marker improvements. None of this constitutes large-scale controlled evidence. Preclinical work is far broader, covering sepsis, inflammatory bowel disease models and autoimmune inflammation, with consistent anti-inflammatory findings. For a reader, VIP is a peptide with real biology and thin clinical data, and any use of it belongs under a clinician's supervision rather than as self-directed dosing.
Preclinical & non-clinical data
A well-characterised neuropeptide regulating smooth muscle, blood vessels and immune cells. Nasal formulations have been studied in sarcoidosis and pulmonary hypertension — specific conditions, not general use.
Non-clinical data comes from cells and animals unless stated otherwise. It answers whether a compound is worth studying in people — not whether it is safe or effective in them.
What users report
Reporting comes largely from people with mast-cell, dysautonomia and chronic-fatigue diagnoses, and the accounts are unusually variable: improved circulation, digestion and energy in some, and wheezing, headaches, flushing or a racing heartbeat after dosing in others. Users frequently note that reactions tracked with the amount used, and several describe abandoning it after one bad dose. This variability is the most consistent feature of the reported experience.
Where these reports come from
These are unverified personal accounts collected from public sources. They are not evidence of effectiveness or safety, they have not been independently checked, and they are not a recommendation to use anything described.
Possible side effects
- Flushing and hypotension, given its vasodilating action
- Headache
- Nasal irritation with intranasal use
- Dizziness
- Rapid heart rate
Safety notes
VIP lowers blood pressure and dilates blood vessels, so it is a particular concern for anyone on antihypertensive medication, with cardiovascular disease, or prone to hypotension. Its short half-life means effects are brief but can be abrupt. There is no long-term safety data for repeated use, and it is not an approved product anywhere for these purposes.
Stacking
Appears in some protocols alongside other immune-modulating compounds. Its hypotensive effect makes unmonitored combinations with blood-pressure medications particularly unwise.
Related compounds
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