THC, or tetrahydrocannabinol, is the chemical responsible for most of marijuana’s psychological effects. It acts much like the cannabinoid chemicals made naturally by the body, according to the National Institute on Drug Abuse (NIDA).
Cannabinoid receptors are concentrated in certain areas of the brain associated with thinking, memory, pleasure, coordination and time perception THC attaches to these receptors and activates them and affects a person’s memory, pleasure, movements, thinking, concentration, coordination, and sensory and time perception, according to NIDA.
THC is one of many compounds found in the resin secreted by glands of the marijuana plant. More of these glands are found around the reproductive organs of the plant than on any other area of the plant. Other compounds unique to marijuana, called cannabinoids, are present in this resin. One cannabinoid, CBD is nonpsychoactive, according to the National Center for Biotechnology and actually blocks the high associated with THC.
Effects on the body
THC stimulates cells in the brain to release dopamine, creating euphoria. It also interferes with how information is processed in the hippocampus, which is part of the brain responsible for forming new memories.
THC can induce hallucinations, change thinking and cause delusions. On average, the effects last about two hours, and kick in 10 to 30 minutes after ingestion. Psychomotor impairment may continue after the perceived high has stopped, however.
British Journal of Pharmacology found that other types of cannabinoids, as well as terpenes (compounds that produce flavor and fragrance in plants), can modulate and reduce negative effects.
The effects of marijuana make it a popular drug. In fact, it is considered one of the most commonly used illicit drugs in the world. But these effects also concern mental health advocates. THC can trigger a relapse in schizophrenic symptoms, according to NIDA.
Another possible risk of consuming THC comes in the form of impaired motor skills. Marijuana may impair driving or similar tasks for approximately three hours after consumption and it is the second-most common psychoactive substance found in drivers, after alcohol, reports the National Highway Traffic Administration. People taking medical marijuana are instructed not to drive until it has been established that they can tolerate it and conduct motor tasks successfully.
The drug can also have drug interactions with certain medications.
According to the National Cancer Institute, marijuana has been used for medicinal purposes for more than 3,000 years. As of early 2017, more than half of the United States has legalized the use of medicinal marijuana. Several states have also legalized the drug for recreational use, as well.
THC can be extracted from marijuana, or synthesized, as is the case for the FDA-approved drug dronabinol. Dronabinol is used to treat or prevent the nausea and vomiting associated with cancer medicines and to increase the appetites of people with AIDS, according to the U.S. National Library of Medicine. It is a light yellow resinous oil.
Other studies are showing more evidence that, when used properly, THC has many additional medical benefits. For example, THC may be able to improve memory when taken in small doses, according to a 2016 study on mice.
People tout marijuana as a better drug than prescription pills because it is “all-natural.” That may not be true. “Just because something is considered ‘natural’ doesn’t mean it’s healthy,” Raskin said. “For example, poison oak can be harmful. Just because it grows in the ground doesn’t mean it’s good for you or healthy.”