Chemical messengers transmit information from nerve cell to nerve cell in the body and the brain. Messages are constantly being sent back and forth with amazing speed. Your nerve cells are called neurons, and their chemical messengers are called neurotransmitters. This communication system can be disrupted by chemicals like hallucinogens, and the results are changes in the way you sense the world around you. Some hallucinogens can be found in plants.
Mescaline comes from a cactus called peyote.
And certain mushrooms, also known as magic mushrooms, are hallucinogens. But many hallucinogens are chemicals that don't occur in nature.