The Health Effects of Cannabis and Cannabinoids

Summary & key facts

Researchers reviewed many studies about recreational cannabis use and its chemicals. They described harms to the body and brain and noted some areas where evidence is uncertain. The review says cannabis can harm thinking and memory, raise heart and lung risks, affect babies if used in pregnancy, and that stronger forms of cannabis today may make these problems more likely. It also notes that one ingredient called CBD is being studied for some medical uses, while THC is the main mind‑changing chemical that causes many of the harms.

Key facts:

• About 120 million people worldwide use cannabis for fun, so any health risks affect a lot of people.
• Cannabis plants contain many chemicals, but the two most studied are THC and CBD. THC causes the “high” and can change perception and memory. CBD often acts in the opposite way and is being tested as a medicine for some seizures and possibly for anxiety or psychosis.
• THC in modern cannabis is much stronger than decades ago. A single joint used to have about 10 mg of THC in the 1970s. Now similar products can contain roughly 60 to 150 mg of THC, and higher strength can increase health risks.
• Starting regular cannabis use in the teen years is linked to lasting problems with learning and memory. One long study found teen users lost about 6 to 8 IQ points as adults, and stopping in adulthood did not fully restore those losses.
• Short-term effects after using cannabis can include anxiety, panic attacks, and psychotic-like symptoms in people who are vulnerable. It also slows reaction time, hurts attention, and harms coordination, which makes driving after using cannabis more dangerous.
• Drivers who had THC in their blood were about twice as likely to cause a crash as drivers impaired by alcohol, according to studies cited in the review.
• Smoking cannabis irritates the lungs. The smoke contains more of some cancer-causing chemicals than tobacco smoke and is linked to chronic bronchitis and other lung problems. Some studies also suggest links to certain cancers and to testicular cancer in young men who used cannabis in adolescence.
• Cannabis affects the heart. Heart rate can jump by about 20 to 50 beats per minute soon after smoking. Some evidence shows the chance of a heart attack may rise up to fivefold in the hour after smoking cannabis. THC also passes to a fetus during pregnancy and builds up in breast milk, and prenatal exposure is linked to lower birth weight and possible developmental effects.

Abstract

Due to growing marijuana and other canabis use there is need to evaluate its safety. Some adverse health effects of cannabinoids recreational use were presented. Both aspects: somatic health as well as mental health issues were discussed.

Topics

Cannabis and Cannabinoid Research

Categories

Health Sciences Medicine Pharmacology

Tags

Cannabidiol Cannabis Effects of cannabis Marijuana smoking Medicine Polysubstance dependence Psychiatry Psychology Substance abuse

Substances

Cannabis

Conditions & symptoms

Addiction Anxiety Substance abuse disorder Addiction or harmful habbits Anxiety or worry Difficulty focusing Sadness or low mood