Effects of Marijuana on the Brain

Marijuana, also known as cannabis or ganja, is obtained from the flowers, leaves and the seeds of the cannabis plant. Hashish is the name of the resinous form of marijuana. It contains almost 60 cannabinoids, the psychoactive compounds, out of which the main active chemical compound is the THC or the delta-9-tetrahydrocannabinol. It has been used by mankind since ancient times. However, a growing trend of its use as a recreational and medicinal drug was witnessed in the 20th century. Its overuse coupled with its adverse effects, especially on the brain and the lungs have induced most of the countries of the world to prohibit the use, possession and sale of this drug.

Effects of Marijuana on the Nervous System

When it is consumed, the active THC compound is carried to the brain by the blood stream. In the brain, it binds with the cannabinoid receptors of the nerve cells and thereby brings about a change in their activities. These cannabinoid receptors are mostly found in those regions of the brain, which control memory, thought, sensation of pleasure, perception and concentration. By altering the activities of the neurons, it adversely affects memory, concentration, thinking capacity and creates a distorted perception.

THC also affects the production and release of the neurotransmitter dopamine, and hence, stimulates certain regions of the brain, which produce a pleasurable excitement. Therefore, individuals using marijuana, feel a sense of elated happiness. It has been observed that the effects produced by its intake last for several days or weeks. After the initial stage of feeling high or elated, the abuser often feels depressed or sleepy. Sometimes, marijuana abuse can also produce anxiety or panic, along with a sense of fear and distrust.

Regular use naturally leads to an addiction. Sudden withdrawal, after using it for a long time, can cause irritability, loss of appetite, sleep deprivation, anxiety, etc. Some researches have suggested a link between marijuana and anxiety, depression, suicidal tendencies and even schizophrenia. As far as a possible association between marijuana use and mental illness is concerned, enough supportive evidence is not available. However, regular use at an early age is presumed to put a person at a higher risk of suffering from mental illnesses. Intake of a high dose of marijuana can cause psychotic reactions like hallucinations and delusions.

Effects on Other Parts of the Body

Besides adversely affecting the brain, marijuana increases blood pressure, heart rate and raises the risk of heart diseases. It also hampers the oxygen carrying capacity of blood. In addition to THC, it contains carcinogens including hydrocarbons. In some studies, an unregulated growth of the epithelial cells in the tissues of the lungs has been observed in the smokers of marijuana. Therefore, it is suspected that marijuana may cause lung cancer, though sufficient evidence is not available to support this association. But, it can cause considerable damage to the liver and respiratory ailments such as cough, lung infections, blockage of the air passages, bronchitis and bronchial asthma.

It directly affects the central nervous system and is a harmful psychoactive substance. Though, the association between mental illness and its consumption has not been proved, it is an undeniable fact that it has an adverse impact on the mental health of an individual. Therefore, besides enforcing strict regulations, creating a general awareness about its disastrous effects is also required to tackle the menace of marijuana abuse.