VIP

Overview

VIP, or vasoactive intestinal peptide, is a naturally occurring 28-amino-acid signaling peptide found in the nervous system, gut, and immune tissue. It is best known for its anti-inflammatory and immunoregulatory activity, and is commonly discussed in the context of chronic inflammatory conditions, mold-related illness, and respiratory support.

Interest in VIP as a therapeutic centers on its synthetic form, aviptadil (also known as RLF-100), which has been studied in humans for conditions such as sarcoidosis, pulmonary hypertension, and acute respiratory failure. It carries orphan-drug designations in some regions but is not an FDA-approved general therapeutic.

Much of the supporting evidence is preclinical or comes from small early-stage clinical studies. Research-grade VIP sold outside of these trials is intended for research use only.

How it works

VIP is described in the literature as a broad regulator of the immune system. In studies it appears to reduce the production of inflammatory cytokines and chemokines from cells such as macrophages and dendritic cells, while shifting immune responses away from inflammatory patterns and supporting regulatory T-cell activity. These effects are thought to be mediated through the VPAC1 and VPAC2 receptors.

In a small clinical study of inhaled VIP in sarcoidosis, treatment was associated with reduced production of an inflammatory cytokine (TNF-alpha) and an increase in regulatory T cells. The exact mechanisms and clinical significance in humans remain an area of ongoing research.

Reported benefits

• Anti-inflammatory activity in chronic inflammatory conditions (studied for sarcoidosis)
• Immune regulation, including support for regulatory T-cell activity
• Respiratory support, studied in conditions such as pulmonary hypertension and asthma
• Interest in mold-related illness and chronic inflammatory response syndrome (limited evidence)

These are reported and studied effects, not guaranteed outcomes.

Considerations & side effects

Because VIP has a very short duration of action in the body and is not well absorbed orally, studies have used inhaled or injectable delivery. Reported effects in trials include flushing, low blood pressure, diarrhea, and irritation at the site of administration; the long-term safety profile outside of monitored clinical settings is not well characterized.

Evidence for many of the popularly discussed uses, including mold illness, remains limited and largely preliminary. Product purity varies in the research-chemical market, and VIP is not a substitute for evaluation and treatment by a qualified clinician.