VIP (Vasoactive Intestinal Peptide)

Most people who search for VIP have already heard of it from one place, the protocol for chronic inflammatory response syndrome, the condition many people call mold illness. VIP is the last step in that protocol, and the reasons people reach for it are the ones that send them looking in the first place: brain fog, fatigue that rest doesn't touch, and the sense that inflammation is running the show. The protocol was developed outside the published research, and the people who follow it report the results themselves.

The second group comes from the lung research. VIP is one of the body's own lung peptides, and it was tested in hospital trials for COVID-19 lung failure and in a small study of sarcoidosis, an inflammatory lung disease. People who read those studies come to it for immune balance and calmer inflammation more broadly.

A smaller group comes through the gut. The peptide was first pulled out of intestinal tissue, which is where the "intestinal" in its name comes from, so people dealing with gut trouble alongside inflammation ask about it too.

Many of the people asking are women in midlife who've spent a long time being told the fog and fatigue are stress, age or nothing at all. That's the reader this page is written for.

VIP is a short chain of 28 amino acids that your own body makes, in the gut, the lungs and the nerves that run between them. Its first job is in the name. "Vasoactive" means it acts on blood vessels, and it relaxes them so they widen and more blood gets through. It was found in 1970, and the paper that described it called it a strong, long-lasting widener of blood vessels.

Its second job is calming. VIP dials down the signals that keep inflammation going, a bit like someone turning down the thermostat in a room that's been running hot for weeks. In the sarcoidosis study, people who inhaled VIP for four weeks had fewer of the cells and signals that drive inflammation in fluid taken from their lungs. That was a small study with no comparison group, so it shows a real effect on the immune system, not a proven benefit.

The manufactured version is called aviptadil. It's the same molecule, and you'll see both names on trial records and vendor pages.

VIP reaches people in two quite different forms, and the difference matters. Research vendors sell it as freeze-dried powder in a vial, 10 mg most often, then 5 mg, which you mix with bacteriostatic water (sterile water with a preservative, so one vial can be drawn from more than once) and inject under the skin. Once it's mixed, a vial keeps for 28 days in the fridge.

The mold illness protocol, on the other hand, uses a compounded prescription nasal spray at 50 mcg a spray, made by compounding pharmacies, not research vendors. Vendors describe 50 mcg under the skin twice a day for the vial, and the only place we could trace that number is the strength of the spray. No study or label sets an injected amount. The hospital trials used a drip in the vein and a nebulizer, so their amounts don't carry over to either.

The VIP dosage chart sets out the injected and nasal patterns side by side, where each one comes from, the units to draw from a 5 mg or 10 mg vial and how much of each vial goes unused before the 28 days run out.

That small amount changes the vial math. At 50 mcg twice a day, a 10 mg vial runs out its 28 days with about 7.2 mg still in it, and a 5 mg vial with about 2.2 mg left, per the dosage page's math. No study or label sets how long a course should run, and eight weeks on is the convention vendor pages repeat, which at that amount means two vials of either size, one for each 28 days. The smaller vial wastes less, even when the bigger one costs less per milligram.

The safety record from the trials is reassuring as far as it goes. In hospital patients with COVID-19 lung failure, no serious side effects were tied to the drug, and the sarcoidosis study reported it as safe and well tolerated over four weeks.

Because VIP widens blood vessels, the effects to expect are the ones that come with that. Flushing, a drop in blood pressure and light-headedness are what people watch for, and they depend on the amount and the route. Anyone already on blood pressure medication, or prone to feeling faint when standing up, has the most reason to start low.

What nobody knows yet is how it behaves in the way it's actually used. None of the human safety data covers injection under the skin, the nasal spray, months of daily use or healthy people. With a research vial there's also the vial itself, which isn't made under drug-maker controls, so look for a vendor that publishes independent lab results for the batch you'll get.

In the biggest hospital trial, aviptadil didn't beat the dummy treatment, and inhaled VIP didn't help high blood pressure in the lungs either. None of those trials studied mold illness, fog or fatigue, so they don't answer the question most buyers have, in either direction.

The spray and the vial carry the same molecule, and they aren't the same product. The compounded spray comes metered, with a preservative system and sterility checks built in, at a fixed 50 mcg a spray. A research vial is powder you mix yourself, so the amount in each dose depends on your math, and how much water you add changes the size of each draw.

Some people mix a research vial into their own nasal spray. That isn't the same as buying the compounded product, and we found no study of how much of a homemade spray gets absorbed. A matching number on two labels doesn't make a spray and an injection equal.

In the US, VIP isn't FDA approved for anything. Aviptadil went through emergency use consideration for COVID-19 lung failure during the pandemic and didn't get approval. Research vendors sell it labeled for research use, and compounding pharmacies make the nasal spray on prescription.

It isn't unapproved everywhere, though. Aviptadil combined with phentolamine is licensed as Invicorp, an injection for erectile dysfunction, in the UK and in Sweden, Denmark, Norway and Finland. That's a different product, for a different use, given a different way, and it doesn't say anything about the uses people buy VIP for.

We haven't written a head-to-head page for VIP yet. The compounds people most often weigh it against are the other immune-calming peptides. Thymosin Alpha-1 is the one studied for steadying the immune system, and its dosage page covers how people pair the two. KPV is the small anti-inflammatory peptide people ask about for the gut and skin.

When you compare VIP prices, compare the cost per milligram across vial sizes, and remember that at 50 mcg twice a day a 10 mg vial expires long before it's empty. The vendor directory shows which sellers publish independent lab results for their batches.

It's sold for research, and the trials that exist studied hospital lungs, not mold illness. You knew that, it's why you're reading this and not the label.