In Nepal, giant bees produce a precious honey that has natural psychoactive properties.

Dubbed the "mad honey," this hallucinogenic nectar is produced by the Himalayan cliff bee, which is the largest bee in the world at about 3 cm long. This rare honey is known for its psychedelic and medicinal properties, and costs five times more than the conventional honey, which is why locals from China and Nepal risk their lives trying to gather it.

The Himalayan cliff bees live in an environment where Rhododendron flowers grow, and these plants contain grayanotoxins, which are poisonous chemicals present in the nectar.

The bees frequently collect this nectar, and the grayanotoxin compound in the nectar transforms the honey into a formula with hallucinogenic and recreational effects. When taken in small doses, the mad honey is intoxicating and gives of a feeling of relaxation followed by pleasant dizziness and tingling sensation.

The honey's hallucinogenic effect is also felt, but there are few scientific literature about its effects.

Locals also use the honey to treat hypertension and diabetes. It is also a renowned aphrodisiac as it cures poor sexual performance.

The mad honey is only effective when taken in small amounts. Higher dosages, however, can be highly toxic and sometimes fatal (to small animals).

In 67 B.C., King Mithridates' army used the mad honey to drug their Roman enemies. While the hallucinogenic effects were kicking in, the army easily attacked and defeated the Roman forces.

But collecting the honey is challenging itself. According to EWAO, the beehives can be found on overhanging rocks on cliffs situated at over 2,500 meters above sea level. The nest is up to 5 feet in diameter and carries up to 60 kg of honey.

These places are extremely difficult to reach, but locals would go to remarkable lengths just to get this rare honey. They would collect two batches of honey every year, in spring and autumn. But it is said that the honey is in its full "madness" during spring time.