Grayanotoxin: The Active Compound in Mad Honey

Grayanotoxin is the natural compound in mad honey responsible for its effects — a group of toxins found in rhododendron nectar that act on the body’s sodium channels. It’s what makes mad honey “mad”: mildly euphoric and warming in small doses, and toxic in large ones. Ordinary honey doesn’t contain it.

This guide explains what grayanotoxin is, how it affects the body, and why its concentration is the single most important thing to know about any jar of mad honey.

What is grayanotoxin?

Grayanotoxin is a family of naturally occurring neurotoxins produced by rhododendron and related plants, which pass into honey when bees forage on their nectar. There are several types, varying in potency, described in detail on Wikipedia’s mad honey entry.

It’s a plant defense compound that ends up in honey by accident of geography — which is why only honey from rhododendron-rich regions contains it.

How does grayanotoxin affect the body?

Grayanotoxin binds to sodium channels in nerve and muscle cells, keeping them open longer than normal, which produces the tingling, warmth, lightheadedness and — in excess — the drop in blood pressure and heart rate seen in mad honey poisoning. The effect is dose-dependent.

At a small dose that action feels pleasant; at a large dose it becomes the mechanism of toxicity. Same compound, very different outcomes.

Why do grayanotoxin levels vary?

Grayanotoxin levels vary by rhododendron species, altitude, season and harvest, so no two batches of mad honey are identical in strength. Spring-harvested, high-altitude Nepali honey tends to be more potent.

This natural variation is exactly why reputable sellers lab-test each batch, and why an untested jar of unknown strength should be dosed cautiously. For example, one published batch report on our own mad honey, Magaranger (tested by Vereenigde Laboratoria Drs. W.H. Nagel B.V., Amsterdam; certificate 2502051, 30 April 2025), measured Grayanotoxin I at 35,038 µg/kg and Grayanotoxin III at 13,520 µg/kg by LC-MS/MS — read the certificate (PDF), or browse our full open lab-report dataset.

Is grayanotoxin dangerous?

Grayanotoxin is safe-feeling in tiny amounts but genuinely toxic in excess, causing “mad honey poisoning” — nausea, dizziness, low blood pressure and slowed heartbeat. It’s rarely fatal in healthy adults and usually resolves within a day, but can be serious for people with heart conditions, as documented in peer-reviewed reviews of mad honey poisoning and an EU risk assessment of grayanotoxins in honey.

Respect it: the dosage guide and our is mad honey safe? guide exist precisely because this is an active compound, not a novelty.

Frequently asked questions

Can you buy grayanotoxin honey? Yes — “grayanotoxin honey” is just mad honey. Buy from sellers that publish the tested level. See where to buy.

Is grayanotoxin the same as THC? No. They’re chemically unrelated; grayanotoxin acts on sodium channels, not cannabinoid receptors — which is why mad honey doesn’t show up on a standard drug test.

How much grayanotoxin is in mad honey? It varies by batch, which is why lab testing matters. There’s no single fixed number.