Vasodilator

vas·o·di·la·tor
vāzōˈdīˌlādər
A vasodilator is a substance or medication that causes the dilation, or widening, of blood vessels. This effect occurs through the relaxation of the smooth muscles within the vessel walls, leading to increased blood flow and reduced vascular resistance. Vasodilators are commonly used to treat conditions such as hypertension, heart failure, and angina by improving circulation and oxygen delivery to tissues.

Relationship to the Blood-Brain Barrier and Psilocybin
The blood-brain barrier (BBB) is a selective, semipermeable barrier that regulates the movement of substances between the bloodstream and the brain, protecting neural tissues from potentially harmful compounds while allowing essential nutrients to pass through. Vasodilators, by increasing blood flow, can influence the dynamics of this barrier. Enhanced circulation may facilitate the delivery of compounds like psilocybin to the brain by increasing the concentration gradient across the BBB.

Psilocybin, a prodrug, is converted into its active form, psilocin, after ingestion. Psilocin, due to its structural similarity to serotonin, crosses the BBB to exert its psychoactive effects by interacting with serotonin receptors in the brain. Vasodilators, such as those naturally found in cacao (e.g., theobromine), may amplify this process by promoting greater blood flow, potentially optimizing the uptake and distribution of psilocin within the central nervous system. This interplay may explain anecdotal reports of enhanced intensity and duration of psilocybin experiences when combined with vasodilatory substances.