Also known as: Vasoactive Intestinal Peptide, aviptadil
A natural neuropeptide used in the Shoemaker protocol for mold illness (CIRS).
Educational reference, not medical advice. Many compounds here are not approved, and products sold as research chemicals are not checked for purity. Plan any use with a licensed clinician.
How it works
Calms immune overactivity, relaxes blood vessels and airways, and regulates hormone signaling.
Evidence by goal
| Goal | Grade | What the grade means |
|---|---|---|
| Immune & infections | C | Limited human data, case series or practitioner reports |
| Stress, anxiety & mood | D | Animal or cell studies only |
At a glance
- Route
- Nasal spray
- Half-life
- About 1 to 2 minutes
Reported dosing
50 mcg per spray, up to 4 times daily (Shoemaker protocol).
Timing: Spread through the day.
Cycle: Weeks to months, with lab monitoring.
From approved labels where they exist, otherwise from published trials and practitioner reports.
Side effects
- Nasal irritation
- Low blood pressure
- Flushing
Who should avoid it
- Ongoing mold exposure (protocol requires removal first)
Often combined with
Final step of the CIRS protocol after binders.
Key findings
An open-label CIRS study reported symptom improvement. IV aviptadil did not meet its main goal in COVID respiratory failure.
Where it is legal (Oct 2026)
| US | Compounded prescription |
|---|---|
| Canada | Not approved |
| Mexico | Not approved |
| EU | Prescription |
EU: aviptadil (Invicorp) is prescribed for erectile dysfunction in some states. US: compounded nasal spray only.
Sources
Open VIP in the Peptide Guide Compare all peptides by goal
Last reviewed November 2026. Regulatory status reflects the US unless noted and changes often.