Marijuana, also known as cannabis, is the most-used substance in the US after alcohol and tobacco.
Research suggests around 10 percent of those who use marijuana may have some degree of a substance use disorder. People who begin using marijuana before the age of 18 are four to seven times more likely to develop a substance use disorder than those who start in adulthood.
What is marijuana?
Marijuana refers to the dried leaves and flowers from the cannabis plant which contain the mind-altering chemical delta-9-tetrahydrocannabinol (THC) and other related compounds.
How Is It Used?
Marijuana can be smoked, vaporized, eaten, and brewed in tea. Other common names for marijuana are weed, pot, and cannabis.
Short-Term Effects
When marijuana is smoked, THC quickly passes from the lungs into the bloodstream, which carries it to the brain and other organs. The body absorbs THC more slowly when the plant is eaten. THC affects brain receptors that ordinarily react to natural THC-like chemicals that play a role in normal brain development and function. Marijuana over-activates parts of the brain that contain the highest number of these receptors, which causes the "high" that people feel.
Short-term effects can include:
altered senses (for example, seeing brighter colors)
altered sense of time
changes in mood
difficulty with attention and problem-solving
impaired memory
increased heart rate
Rare side effects that can occur when THC is taken at very high doses include:
hallucinations
delusions
psychosis
Long-Term Health Consequences
Smoking marijuana can cause breathing problems similar to those caused by smoking tobacco--such as frequent cough and phlegm and a higher risk of lung infections. Researchers have not yet found a higher risk for lung cancer in people who smoke marijuana. (NIDA)
Marijuana use during pregnancy is linked to lower birth weight and increased risk of brain and behavioral problems in babies.
Long-term marijuana consumption has been linked to mental illness in some users, such as:
worsening symptoms in patients with schizophrenia and bipolar disorder
increased rates of depression and social anxiety disorder
Regular use of marijuana by adolescents may impair brain development have long-term impacts on learning and memory.
Marijuana Use Disorder Treatments
Marijuana use disorder appears to be very similar to other substance use disorders, although the long-term clinical outcomes may be less severe. (NIDA)
Cognitive-behavioral therapy, contingency management, and motivational enhancement therapy have all shown promise in the treatment of marijuana use disorder.
Currently, the FDA has not approved any medications for the treatment of marijuana use disorder, but research is active in this area.