Cannabis or Marijuana is highly abused illegal drug in United States. According to National Survey on Drug Use and Health (NSDUH) report, more than 15.2 million people were abusing Cannabis in 2008. Cannabis abuse is linked with many negative effects, both physically and mentally, sometimes involving violence and injury. Many people are getting addicted to Cannabis unaware of its harmful effects. Following are the harmful effects of Cannabis abuse:

Effects on general health

There are many effects of Cannabis on general health. It mainly effects immune system, respiratory system, cardiovascular system and neurological system. The Cannabis almost affects every system in the body. The general health effects of cannabis are:

• Somatic effects

Somatic effects of Cannabis abuse include decrease in blood pressure, increased heart rate, red eyes, dry mouth, dilation of blood vessels in eyes causing redness, reduced intra-occular pressure, enlargement of pupils, sensation of cold or hot hands and feet, increased craving for food.

• Heart attack

There is a high risk of heart attack in Cannabis smokers. The inhalation of the smoke increases the heart rate from 20 to 50 percent. The heart rate may remain high for about 2 hours. It also results in reduced oxygen carrying capacity of blood. Due to this, there will be complex changes in blood pressure and may result in heart attack.

• Effects on lungs

Cannabis abusers have problems of rapid lung destruction. The carcinogenic hydrocarbons present in Marijuana increases the risk of cancer among its abusers. Cannabis abuse can cause acute and chronic bronchitis, stinging of mouth and throat accompanied by cough, cough along with phlegm production, more frequent chest illnesses, higher risk of lung infections, obstructed airways, emphysema.

• Causes cancer

Cannabis smoke has 50 to 70 percent more carcinogens when compared to tobacco smoke. Cannabis smokers are more prone to lung and neck cancer compared to cigarette smokers. One Cannabis joint smoking is said to be equivalent to 20 cigarettes.

Effects on mental health

Cannabis abuse can cause mental illnesses or it worsens the existing psychotic symptoms. THC, a psychoactive chemical present in Marijuana, has deteriorating effects on brain. The THC, once inhaled, passes from lungs into blood stream and reaches brain. The THC molecules on reaching brain bind to cannabinoid receptors and impair its functioning. On prolonged abuse of Cannabis, there will be mental illnesses, mood swings etc.,

• Psychoactive effects

Psychoactive effects of Cannabis mainly depends on the amount of intake of drug, environment and health of a person. Cannabis intake gives 'high' like euphoria or altered state of consciousness. The drug abuser will have enhanced appreciation for music, humor, colors appear more intense, nostalgia, improvement of working of senses. Cannabis abuse will result in anxiety, irritability, paranoia, agitation, suicidal ideation, depression, schizophrenia, distorted perceptions, impaired co-ordination, lack of interest and concentration, lack of problem solving ability.

• Neurological effects

Cannabis has adverse effects on nervous system of a person. THC chemicals present in Cannabis attach to cannabinoid receptors in the brain. These chemicals interfere with the communication between neurons. These chemicals affect the region called hippocampus and results in short term memory loss. They also result in alteration in behavioral pattern of a abuser.

Effects on oral health

Cannabis abusers have very poor oral health and hygiene. They have increased risks of dental carries and periodontal diseases. Abusers are majorly prone to several oral infections because of the immunosuppressing ability of Cannabis. Cannabis smoking and chewing causes Cannabis stomatitis (chronic inflammation orally), white patches in the mouth (leukoplakia), thickening of oral skin (hyperkeratosis). Cannabis abuse results in pre-malignant (cancerous) lesions in the mouth. Ultimately, Cannabis abuse results in oral cancer.