VIP
Vasoactive Intestinal Peptide · Neuropeptide
Vasoactive Intestinal Peptide (VIP) is a 28-amino acid neuropeptide belonging to the glucagon/secretin superfamily. It is produced in many tissues including the gut, pancreas, and brain. VIP has potent vasodilatory, anti-inflammatory, and immunomodulatory effects. It binds to VPAC1 and VPAC2 receptors, triggering cAMP-mediated signaling cascades. Research shows therapeutic potential for pulmonary hypertension, diabetes, neurological disorders, and autoimmune conditions.
Overview
Vasoactive Intestinal Peptide (VIP) is a 28-amino acid neuropeptide belonging to the glucagon/secretin superfamily. It is produced in many tissues including the gut, pancreas, and brain. VIP has potent vasodilatory, anti-inflammatory, and immunomodulatory effects. It binds to VPAC1 and VPAC2 receptors, triggering cAMP-mediated signaling cascades. Research shows therapeutic potential for pulmonary hypertension, diabetes, neurological disorders, and autoimmune conditions.
VIP binds to VPAC1 and VPAC2 G protein-coupled receptors, activating adenylyl cyclase and increasing intracellular cAMP and PKA activity. This triggers phosphorylation of CREB and other transcription factors. VIP causes vasodilation through NO-dependent and independent mechanisms, stimulates intestinal secretion, relaxes smooth muscle, inhibits gastric acid secretion, and has positive inotropic/chronotropic cardiac effects.
Research indications
What the compound has been studied for, grouped by body system. Effect size is the reported magnitude where it was measured — not a recommendation.
VIP inhalation shows striking efficacy with increased mixed venous oxygen saturation and exercise capacity.
Dilates peripheral blood vessels through NO-dependent mechanisms above 100 pmol doses.
Coronary vasodilation with positive inotropic and chronotropic effects on the heart.
Promising therapeutic target for Alzheimer's, Parkinson's, and other neurological disorders.
Potential therapeutic target being researched for ASD.
Produced in suprachiasmatic nuclei; involved in circadian regulation.
Promotes insulin secretion in glucose-dependent manner via VPAC2; low hypoglycemia risk.
Potent anti-inflammatory effects useful in IBD and autoimmune conditions.
Therapeutic potential for pulmonary and systemic sarcoidosis.
A large effect in a weak study and a small effect in a strong one are different things. Effect size is never evidence of use in people.
- Class
- Neuropeptide
- Chain length
- 28 residues
- Molecular weight
- 3326 Da
- Half-life
- ~2 min
- Typical dose
- 50-100 mcg per dose (up to 200 mcg in research protocols)
- Frequency
- 1-2 times daily due to very short 2-minute half-life
- Cycle length
- As prescribed for specific condition
- Storage
- Lyophilized powder: 2-8°C refrigerated; Reconstituted: use immediately (very short stability, ~2 minute half-life)
Molecular data
- Type
- Neuropeptide
- Molecular weight
- 3326 Da
- Chain length
- 28 residues
- Half-life
- 2 min
Dosing reference
Doses reported in the literature and by suppliers. These are a record of what has been used in research — reference, never instruction.
| Context | Route | Amount | Frequency |
|---|---|---|---|
| General use | SubQ or IV | 50-100 mcg | 1-2x daily |
| Research protocols | SubQ or IV | 100-200 mcg | As directed |
| Pulmonary hypertension | Inhalation | 100-200 mcg/day | Daily (inhaled) |
Interactions
No known negative interactions; different mechanisms.
Both have immunomodulatory effects; may complement each other.
Both have anti-inflammatory properties.
Quality checklist
- ✓White lyophilized powder
- ✓Clear solution after reconstitution
- ✓Intact vacuum seal
- !Use quickly after reconstitution (unstable)
- ×Discolored powder
- ×Cloudy solution
- ×Particulates visible
What to expect
Safety
- Vasodilation (flushing, warmth)
- Hypotension
- Increased heart rate
- Gastrointestinal effects (diarrhea possible)
- Headache
- Severe hypotension
- Allergic reaction symptoms
- Severe diarrhea
- Cardiac arrhythmias
- Severe hypotension
- VIPoma or related tumors
- Pregnancy or breastfeeding
- Severe cardiac conditions
FAQ
How effective is VIP for pulmonary hypertension and can it replace conventional treatments?
VIP inhalation showed striking efficacy with increased mixed venous oxygen saturation and exercise capacity in pulmonary hypertension patients. However, it's complementary to conventional therapy rather than a replacement - the very short 2-minute half-life requires frequent dosing, making it challenging for long-term use without newer stabilized analogs.
Does VIP cause dangerous hypotension or can it be used safely in most patients?
VIP's vasodilation can cause hypotension and flushing, especially at higher doses. Careful dose titration and patient monitoring are essential. Patients with baseline hypotension or severe cardiac conditions should avoid use, but mild transient vasodilation is manageable in most populations with proper medical supervision.
Why is VIP rarely used clinically if research shows such promise?
VIP's extremely short 1-2 minute half-life makes it impractical for routine clinical use - requiring constant infusions or multiple daily injections. Stabilized analogs (like stearyl-Nle17-VIP) are 100-fold more potent but rarely available outside research settings. Limited commercial development has restricted clinical availability despite strong research foundation.
Can VIP improve insulin secretion for diabetes without causing hypoglycemia?
Yes, VIP promotes glucose-dependent insulin secretion via VPAC2 receptors, meaning it only stimulates insulin when blood glucose is elevated. This glucose-dependent mechanism makes hypoglycemia risk very low compared to other insulin secretagogues, making VIP theoretically safer for diabetes support.