Cannabis is a term that refers to marijuana and other drugs made from the same plant. Marijuana is a green, brown, or gray mixture of dried, shredded leaves, stems, seeds, and flowers of the hemp plant (Cannabis sativa). Other forms of cannabis include sinsemilla, hashish, and hash oil. All forms of cannabis are mind-altering (psychoactive) drugs.

The main active chemical in marijuana is THC (delta-9-tetrahydrocannabinol). Short-term effects of marijuana use include problems with memory and learning, distorted perception, difficulty in thinking and problem solving, loss of coordination, increased heart rate, and anxiety.

Marijuana is usually smoked as a cigarette (called a joint) or in a pipe or bong.

Marijuana abuse is associated with many detrimental health effects. These effects can include frequent respiratory infections, impaired memory and learning, increased heart rate, anxiety, panic attacks and tolerance. Marijuana meets the criteria for an addictive drug and animal studies suggest marijuana causes physical dependence and some people report withdrawal symptoms.

Someone who smokes marijuana regularly may have many of the same respiratory problems that tobacco smokers do, such as daily cough and phlegm production, more frequent acute chest illnesses, a heightened risk of lung infections, and a greater tendency toward obstructed airways. Cancer of the respiratory tract and lungs may also be promoted by marijuana smoke. Marijuana has the potential to promote cancer of the lungs and other parts of the respiratory tract because marijuana smoke contains 50 percent to 70 percent more carcinogenic hydrocarbons than does tobacco smoke.

Marijuana's damage to short-term memory seems to occur because THC alters the way in which information is processed by the hippocampus, a brain area responsible for memory formation

According to the 2004 National Household Survey on Drugs, cannabis is the most commonly used illicit drug in Australia. It has many health and safety issues and can no longer be called ‘safe’.

Did you know that:

  • Babies born to mothers who use marijuana during pregnancy have eleven times the risk of getting childhood leukemia. These children are the innocent victims of their parents marijuana use. Based on research by Dr. L. Robison in the publication Cancer and Dr. J. Buckley in Cannabis: Physiopathology, Epidemiology, Detection.
  • Marijuana smoke produces airway injury, acute and chronic bronchitis, lung inflammation, and decreased pulmonary defences against infection. Smoking one marijuana cigarette leads to airway deposition of four times as much cancer-causing tar as does tobacco smoke. Based on research by Dr. D. Tashkin as reported in the Western Journal of Medicine.
  • Cases of cancer, including cancer of the mouth, tongue, larynx, jaw, head, neck, and lungs have been reported in young marijuana smokers that would not occur in tobacco smokers until much later in life. Based on research by reported in Otolaryngology, Head & Neck Surgery, the Journal of the American Medical Association and Southern Medical Journal.
  • Marijuana has long been known to trigger attacks of mental illness, such as bipolar (manic-depressive) psychosis and schizophrenia. It has been shown that marijuana users are six times more likely to develop schizophrenia than are non-users. Based on research by of Dr. S. Andreasson published in Britain's The Lancet.
  • The use of marijuana leads to the use of other drugs. Of those who use marijuana 3 to 10 times, 20% go on to use cocaine. Of those who use marijuana one hundred or more times, 75% go on to use cocaine. Based on research by as reported in the Journal of Clinical Psychiatry.
  • Marijuana causes both dependence and addiction. Addictive use is defined by compulsive repeated use in spite of adverse consequences. Marijuana's effects include tolerance leading to dependence and inability to cease use. Based on research by of Dr. Mark Gold published in his book Marijuana.
  • It's not just alcohol that caused impaired accidents. A roadside study of reckless drivers who were not impaired by
    alcohol, showed that 45% of these drivers tested positive for marijuana. Based on research by of Dr. Dan Brookoff, published in the New England Journal of Medicine.
  • The effects of marijuana persist much longer than the effects of alcohol. Using a computerised flight simulator, an experiment on pilots showed that their ability to land a plane was still impaired 24 hours after smoking one marijuana cigarette. Based on research by of Dr. V. Leirer in Aviation, Space & Environmental Medicine.
  • Children exposed to marijuana prenatally have increased behavioural problems, and they have decreased visual perception, language comprehension, attention span and memory. These children are the innocent victims of their parents marijuana use. Based on research by of Dr. Peter Fried of the Ottawa Prenatal Prospective Study
  • In males marijuana use diminishes testosterone production and lowers sperm count. In females, marijuana use disrupts hormone cycles. Marijuana is mutagenic, fetotoxic (poisonous to the foetus) and impairs RNA and DNA synthesis. Based on research by of Dr. Mark Gold in his book Marijuana and Drs. Latour and Nahas in the Medical Journal of Australia.
  • Cases of cancer from marijuana use are now well documented. In one California study 90% of young cancer patients are marijuana smokers compared with 40% of young people in California as a whole. Based on research by Dr. P. Donald in Otolaryngology, Head and Neck Surgery .
  • In a survey of one hundred and fifty marijuana using students, 59% surveyed report they sometimes forget what a conversation is about before it has ended. 41% report that if they read while stoned they remembered less of what they had read hours later. Based on research by of Dr. Richard Schwartz, Vienna Pediatric Associates in Psychiatric Annals.
  • Long-term use of marijuana may cause irreversible memory problems. Marijuana users find it more difficult to separate irrelevant information from the relevant, their reaction times are longer and electrical activity of the brain is slowed. Based on research by from Macquarie University, Sydney in conjunction with Australia's National Drug & Alcohol Research Centre.
  • There are significant negative effects of prenatal marijuana exposure on the performance of children in standard
    intelligence tests. On average children exposed prenatally to marijuana will have a lower IQ compared to children who are not exposed. Based on research by of Dr. Day et al, in Neurotoxicology and Teratology.
  • Fetal Marijuana Symptoms are similar to Fetal Alcohol Syndrome are two diseases children are born with that are totally preventable. One of the leading specialists in cellular heredity, Dr. Akira Morishima of Columbia University, has said that in his 20 years of research on human cells he has never found any other drug, including heroin, which comes close to the DNA damage caused by marijuana.
  • Saying nobody ever died from smoking marijuana is like saying nobody ever died from smoking tobacco. Marijuana contains the same cancer causing chemicals as tobacco. Marijuana contains acetone, hydrogen cyanide, ammonia, carbon monoxide, benzene, benzo pyrene, nitrosamines and many other cancer causing pollutants. Based on research by of G. Huber in Pharmacology Biochemistry and Behaviour.
  • Marijuana causes many mental disorders, including acute toxic psychosis, panic attacks, flashbacks, delusions, depersonalisation, hallucinations, paranoia, depression and "uncontrollable feelings of aggression". Based on research by of Dr. Richard Schwartz, Vienna Pediatrics Associates in Pediatric Clinics of North America.

Symptoms of use (for concerned parents):

Dr Ingrid Lantner, a pediatrician and an expert on marijuana use among teenagers, notes these common symptoms of the chronic marijuana-using youngster: red eyes (often "handled" with eye drops, which can be a clue to pot use)... constant fatigue... uncalled for irritability and edginess (the "don't hassle me!" syndrome)... caring less about everything ("the drop-out syndrome") with a resultant drop in school grades... abrupt and unexplained mood changes... increasing friction with peers and family... feelings of paranoia... impaired ability to concentrate and loss of short term memory... flat, expressionless speech... lack of interest in grooming and appearance... increases difficulty in fighting off common infections... cough, asthmatic wheezing, chest pains... skin rashes... irregular menstrual cycle... distorted time sense (when asked to raise a hand in 60 seconds or less... and, of course, impaired driving ability.

It is important for parents to realise that, unlike the alcohol user, most pot-smoking youngsters are able to "come down" from a high and act normally when parents are around. Thus many parents of chronic pot-smoking youngsters may remain unaware of this fact for several years.

Also, in the words of Dr. Dean Parmelee, director of the Adolesence In-patient Services at Charles River Hospital, a teaching affiliate of Boston University School of Medicine:

"Some youngsters show some symptoms of chronic marijuana use; some show other symptoms. And some bright youngsters with outgoing personalities seem to be able to maintain their grades and activities for a few years-although gradually all users, youngsters and adults, compromise their potential, their activities and their lifestyles".

In other words, your teenagers may have no apparent symptoms of marijuana impairment. Except in one area. Driving. No matter how well they tolerate, adjust to or compensate for their pot use in other areas, over 70 research studies show that pot-induced driving impairments remain. And they are dose related. The more one smokes and the more potent the pot, the worse the driving impairments.

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