Marijuana and hashish are produced from the hemp plant, cannabis. As a psychoactive agent, it is used primarily to produce euphoria followed by relaxation. Cannabis is known by many names: marijuana, hash, pot, herb, weed, grass, ganja, or dope. Cannabis is usually smoked as cigarettes (joint, nail) or in a pipe (bong). The strength of the end product that comes from the hemp plant vary, owing to the climate and soil in which it is grown and the method of cultivation and preparation. Its potency and quality depend mainly on the type of plant that is grown. Bhang is identified as the least potent and cheapest and is made from the cut tops of uncultivated plants that contain low-resin content. Ganja is derived from the flowering tops and leaves of selected plants that have been carefully cultivated having a high content of resin and, therefore, being more potentiated to the user. Charas is the highest grade and is produced from the resin itself, obtained from fully mature plants. This highly potentiated source is generally referred to as hashish. Additionally, clandestine laboratories have developed a method of producing a liquid called ”hash oil,” which has been found to have more than 60% THC content compared with an average 30% in regular hashish. Psychoactive Effects: Smoking of cannabis can produce relaxation following, euphoria, loss of appetite, impaired memory, loss of concentration and knowledge retention, loss of coordination, as well as a more vivid sense of taste, sight, smell, and hearing. Stronger doses cause fluctuation of emotions, fragmentary thoughts, disoriented behavior, and psychosis. It may also cause irritation to the lungs and respiratory system and cancer. The short-term effects of marijuana include problems with memory and learning, distorted perception, difficulty in thinking and problem solving, loss of coordination, and increased heart rate. Long-term marijuana abuse indicates some changes in the brain similar to those seen after long term abuse of other major drugs. Effects on the body: Cannabis is generally smoked in a cigarette called a joint or a doobie. A marijuana cigarette contains 421 chemicals before ignition. There are 61 cannabanoids, including delta-1 tetrahydrocannabinol, which is the psychoactive agent. Neuroscience research findings have indicated the effects of this psychoactive agent on the modulation of mediotemporal and ventrostraital functions of the brain. There are also 50 different waxy hydrocarbons, 103 terpines, 12 fatty acids, 11 steroids, 20 nitrogen compounds, as well as carbon monoxide, ammonia, acetone, benzene, benzathracene, and benzoprene. When ignited, these chemicals convert into more than 2,000 other chemicals. As these are metabolized by the body, they convert to about 600 chemical metabolites. Cannabinoids have a half-life of 72 hours in the human body. When ingested, effects appear to be dose-dependent. Cannabinoids are lipid-soluble and store at megamicroscopic levels for indefinite periods of time in the body. Early research findings on cannabis have been mixed. However, more recent neuroscience research using structural imaging findings on CT or MR imaging, and conventional angiography clearly indicates that excessive use of cannabis leads to functional or structural impairment of the central nervous system. Chemicals found in marijuana and hashish are believed to interfere with the cell's ability to manufacture pivotal molecules, which grossly affects the substances necessary for cell division including DNA, RNA, and proteins. This causes an ”aging process” in particular clusters of cells found in the brain, liver, lungs, spleen, lymphoid tissues, and sex organs. One well-confirmed danger of heavy, long-term use is its ability to damage the lungs due to the fact that it burns 16 times ”hotter” than tobacco and produces twice as many mutagens (agents that cause permanent changes in genetic material). Biopsies have confirmed that cannabis smokers may be at an extremely high risk for the development of lung diseases including bronchitis, emphysema, and cancer. It is believed that some of marijuana's adverse health effects may occur because THC impairs the immune system's ability to fight disease. There is a prevalence of studies supporting the biological association of marijuana smoking with lung cancer. It is believed that long-term marijuana use causes mental or emotional deterioration. Amotivational syndrome, which includes symptoms of passivity, aimlessness, apathy, uncommunicativeness, and lack of ambition, has been attributed to prolonged marijuana use. Marijuana has the potential to cause problems in daily life or make a person's existing problems worse with depression, anxiety, and personality disturbances exacerbated with chronic marijuana use. One still needs to ask whether these symptoms result from the use of marijuana, the personality characteristics of heavy drug users—bored, anxious, depressed, listless, cynical, and rebellious or a combination. Marijuana has also been looked on as the “gateway drug,” or precursor to use of other, more dangerous drugs. Anyone who uses one drug may be interested in others for the same reasons. Users of one drug often find themselves in the company of users of other drugs, and therefore making them readily available. Marijuana smoke contains some of the same cancer-causing compounds as tobacco, usually in higher concentrations. Someone who smokes five joints per day may be taking in as many cancer- causing chemicals as someone who smokes a full pack of cigarettes every day. Cancer of the respiratory tract and lungs may be promoted by marijuana smoke, since it contains irritants and carcinogens. Tobacco smoke and marijuana smoke may work together to change the tissues that line the respiratory tract. Marijuana smoking could contribute to early development of head and neck cancer in some people. Smoking marijuana has been linked to testicular cancer. Long-term health risks of marijuana use include immune system effects, cardiovascular effects, respiratory effects, reproductive effects, behavioral effects, and cancer. Marijuana use also puts users at risk for various types of accidents. Coinciding with the increasing rates of cannabis use due to medical marijuana has been the recognition of a new clinical condition known as cannabinoid hyperemesis syndrome. This syndrome is characterized by cyclic episodes of nausea and vomiting and abdominal pain. Despite the well established antiemetic properties of marijuana, there is increasing evidence of its paradoxical effects on the gastrointestinal tract and central nervous system. Long-term cannabis use can impair the immune system’s ability to fight off microbial and viral infections. Both animal and human studies have shown that marijuana impairs the ability of T-cells in the lungs’ immune defense system to fight off some infections. Users with preexisting coronary artery disease or cerebrovascular disease may experience myocardial infarctions, congestive heart failure, or stroke. Peripheral vasodilatation causes postural hypotension, which may lead to dizziness or syncope. Cannabis arteritis is a very rare peripheral vascular disease similar to Buerger’s disease. High doses of THC cause a drop in testosterone level, decreased sperm production, and compro- mised sperm motility and viability. THC alters the normal ovulatory cycle by decreasing follicle-stimulating hormone, luteinizing hormone, and prolactin secretion. It crosses the placenta and impairs placental development, fetal nourishment, and placental gas exchange. For this reason, it is implicated in low birth weight, growth restriction, preeclampsia, spontaneous miscarriage, and stillbirth. It also accumu- lates in breast milk. Children of chronic users (greater than five joints per week) were found to have lower verbal and memory scores at age 2 years. A possible increased risk of nonlymphoblastic leukemia, rhabdomyosarcoma, and astrocytoma exists in children whose mothers use cannabis during their pregnancies. Psychiatric/Behavioral Long-term use of marijuana also can lead to a series of attitude and personality changes known as “amotivational syndrome.” This syndrome is characterized by a diminished ability to carry out long-term plans, a sense of apathy, decreased attention to appearance and behavior, and decreased ability to concentrate for long periods of time. These changes can also include poor performance in school. Long-term marijuana use has been shown to cause a decline in IQ of up to eight points. Marijuana use can cause relationship problems and antisocial behavior, such as lying and stealing money. It leads to lower life satisfaction, financial difficulties, and a greater chance of being unemployed. Marijuana use has been shown to increase the risk of schizophrenia two fold in vulnerable individuals. Tolerance and dependence: Many individuals who develop a dependency on marijuana are susceptible to other dependencies because of anxiety, depression, or feelings of inadequacy. In general, there appears to be both a psychological and physical potential for dependency. Signs of possible misuse of marijuana include animated behavior and loud talking, followed by sleepiness, dilated pupils and bloodshot eyes, distortions in perception, hallucinations, distortions in depth and time perception, and loss of coordination. An overdose of marijuana can cause fatigue, lack of coordination, paranoia, and psychosis. Withdrawal: Studies since the 1970s have suggested a marijuana withdrawal syndrome, characterized by insomnia, restlessness, loss of appetite, and irritability. A 1999 study conducted at Harvard Medical School confirmed higher levels of aggression in marijuana users during withdrawal when compared with the infrequent or former marijuana user. Research also reported by Bartholomew et al. (2010) indicated that cannabinoid (THC or synthetic forms of THC) withdrawal in chronically exposed animals leads to an increase in the activation of the stress-response system and changes in the activity of nerve cells containing dopamine. It should be noted that dopamine neurons are involved in the regulation of motivation and reward, and are directly or indirectly affected by all drugs of abuse including cannabis.