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How does Marijuana work?

Marijuana contains chemicals that work by binding to specific sites in the brain and on the nerves.

Are there safety concerns?

Marijuana extract is POSSIBLY SAFE when used as a standardized spray (Sativex, GW Pharmaceuticals) that is applied under the tongue.

Marijuana is POSSIBLY UNSAFE when smoked. Smoking marijuana is associated with an increased the risk of developing lung cancer. Also, some reports suggest that smoking marijuana might cause air-filled cavities to form within lung tissue. These air-filled cavities can cause symptoms such as chest pressure, soreness, and difficulty breathing.

Smoking marijuana or using mouth sprays containing marijuana extract can cause headache, dizziness, drowsiness, dry mouth, nausea, and paranoid thinking. Smoking marijuana might also increase appetite, cause coughs, increase heart rate, increase or decrease blood pressure, and impair mental functioning. Some reports suggest that smoking marijuana may also increase the risk of acute coronary syndrome, heart attack, and/or swelling of walls of the arteries (arteritis). However, in many cases, people who experienced these events after smoking marijuana had other risk factors for heart-related events such as smoking cigarettes or being overweight.

Special Precautions & Warnings:

Pregnancy: Marijuana is UNSAFE when taken by mouth or smoked during pregnancy. Marijuana passes through the placenta and can slow the growth of the fetus. Marijuana use during pregnancy is also associated with childhood leukemia and abnormalities in the fetus.

Breast-feeding: Using marijuana, either by mouth or by inhalation is LIKELY UNSAFE during breast-feeding. The dronabinol (THC) in marijuana passes into breast milk and extensive marijuana use during breast-feeding may result in slowed development in the baby.

Bipolar disorder: Using marijuana might worsen manic symptoms in people with bipolar disorder.

Heart disease: Marijuana might cause rapid heartbeat, short-term high blood pressure. It might also increase the risk of a having heart attack.

A weakened immune system: Cannabinoids in marijuana can weaken the immune system, which might make it more difficult for the body to fight infections.

Depression: Marijuana use, especially frequent use, might worsen symptoms of depression.

Multiple sclerosis: Taking marijuana by mouth might worsen some symptoms of multiple sclerosis.

Lung diseases: Long-term use of marijuana can make lung problems worse. Regular, long-term marijuana use has been associated with lung cancer and also with several cases of an unusual type of emphysema, a lung disease.

Schizophrenia: Using marijuana might worsen symptoms of schizophrenia.

Stroke: Using marijuana after having a stroke might increase the risk of having a second stroke.

Surgery: Marijuana affects the central nervous system. It might slow the central nervous system too much when combined with anesthesia and other medications during and after surgery. Stop using marijuana at least 2 weeks before a scheduled surgery.

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