People who use these drugs a lot may have a hard time concentrating, communicating, or telling the difference between reality and illusion. 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.
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. A Recent Discovery MDMA and MDA cause neurons to release a neurotransmitter called serotonin. Serotonin is important to many types of nerve cells, including cells that receive sensory information and cells that control sleeping and emotions.