April 8, 2013 | Weed. Herb. Rope. Skunk. The names are ever-changing and often change on a daily basis but no matter what it’s called, marijuana remains the most common illicit drug used in the United States. After a period of decline in the last decade, the use of marijuana has generally increased among young people since 2007, corresponding to a diminishing perception of the drug’s risks. In fact, more teenagers are now current smokers of marijuana than of cigarettes, according to the National Institute on Drug Abuse. A 2012 survey of high-school seniors found that 22.9 percent of those surveyed were current marijuana smoker while 17.1 percent were current cigarette smokers. Typically smoked in hand-rolled cigarettes or in pipes, marijuana can also be smoked in blunts, cigars that have been emptied of tobacco and refilled with a mixture of marijuana and tobacco. Marijuana, which has a pungent and distinctive odor, can also be mixed in food or brewed as a tea.

April 8, 2013 | Delta-9-tetrahydrocannabinol, or THC, is the main active ingredient in marijuana. When marijuana is smoked, THC passes from the lungs into the bloodstream, which carries the chemical throughout the body, including the brain. THC acts upon specific molecular targets on brain cells, called cannabinoid receptors. These receptors are ordinarily activated by chemicals similar to THC called endocannabinoids. These are naturally occurring in the body and are part of a neural communication network that plays an important role in normal brain development and function. The highest density of cannabinoid receptors is found in parts of the brain that influence thinking, concentration and coordinated movement. Marijuana overactivates the endocannabinoid system, causing the high and other effects that users experience, such as impaired coordination, difficulty with thinking and problem solving and disrupted learning and memory.

April 8, 2013 | Research has shown that marijuana has the potential to cause problems in daily life or make a person’s existing problems worse. In fact, heavy marijuana users generally report lower life satisfaction, poorer mental and physical health, relationship problems and less academic and career success compared to their peers who came from similar backgrounds. For example, marijuana use is associated with a higher likelihood of dropping out of school. Several studies also associate workers’ marijuana smoking with increased absences, tardiness, workers’ compensation claims and job turnover. Because it seriously impairs judgment and motor coordination, marijuana also contributes to auto accidents. A recent analysis of data from several studies found that marijuana use more than doubles a driver’s risk of being in an accident. And the combination of marijuana and alcohol is worse than either substance alone with respect to driving impairment.

April 8, 2013 | Although many have called for the legalization of marijuana to treat the pain and nausea caused by cancer and other conditions, the scientific evidence to date is not sufficient for the plant to gain approval by the Food and Drug Administration for two reasons. First, there have not been enough clinical trials showing that marijuana’s benefits outweigh its risks in patients with the symptoms it is meant to treat. The FDA requires carefully conducted studies in large numbers of patients to assess the benefits and risks of a potential medication. Also, to be considered a legitimate medicine, a substance must have well-defined and measureable ingredients that are consistent from one unit, such as a pill or injection, to the next. This consistency allows doctors to determine the dose and frequency. As marijuana contains hundreds of chemicals that may have different effects and vary from plant to plant, its use as a medicine is hard to evaluate.

April 8, 2013 | Despite what many may believe, marijuana is addictive. Estimates from research suggest that about nine percent of users become addicted to marijuana. This number increases to 17 percent among those who start young and anywhere from 25 to 50 percent of daily users. Long-term marijuana users trying to quit report withdrawal symptoms including sleeplessness, decreased appetite, anxiety and irritability, all of which can make it difficult to remain abstinent. Behavioral interventions, including cognitive-behavioral therapy and motivational incentives, such as providing vouchers for goods or services to patients who remain abstinent, have been found to be effective in treating marijuana addiction. Although no medications are currently available, recent discoveries about the workings of the endocannabinoid system offer promise for the development of medications to ease withdrawal, block the intoxicating effects of marijuana, and prevent relapse.