http://www.sciencedaily.com/news/mind_brain/marijuana/ Medical research on marijuana. How does marijuana affect the brain? What are some of the risks? Could ingredients in marijuana treat disease? Read this and more. en-us Wed, 15 Feb 2012 21:05:01 EST Wed, 15 Feb 2012 21:05:01 EST 60 http://www.sciencedaily.com/images/logosmall.gif http://www.sciencedaily.com/news/mind_brain/marijuana/ For more science articles, visit ScienceDaily. http://www.sciencedaily.com/releases/2012/02/120210111254.htm Drivers who consume cannabis within three hours of driving are nearly twice as likely to cause a vehicle collision as those who are not under the influence of drugs or alcohol, according to a new review. Fri, 10 Feb 2012 11:12:12 EST http://www.sciencedaily.com/releases/2012/02/120210111254.htm http://www.sciencedaily.com/releases/2012/01/120110163444.htm Using marijuana carries legal risks, but the consequences of occasionally lighting up do not include long-term loss of lung function, according to a new study. In the study in which participants had repeated measurements of lung function over 20 years, occasional and low cumulative marijuana use was not associated with adverse effects on pulmonary function. Tue, 10 Jan 2012 16:34:34 EST http://www.sciencedaily.com/releases/2012/01/120110163444.htm http://www.sciencedaily.com/releases/2012/01/120102180854.htm Different ingredients in marijuana appear to affect regions of the brain differently during brain processing functions involving responses to certain visual stimuli and tasks, according to a new report. Mon, 02 Jan 2012 18:08:08 EST http://www.sciencedaily.com/releases/2012/01/120102180854.htm http://www.sciencedaily.com/releases/2011/12/111214125906.htm Cigarette and alcohol use by eighth, 10th and 12th-graders are at their lowest point since the Monitoring the Future survey began polling teenagers in 1975, according to this year's survey results. However, this positive news is tempered by a slowing rate of decline in teen smoking as well as continued high rates of abuse of other tobacco products (e.g., hookahs, small cigars, smokeless tobacco), marijuana and prescription drugs. Wed, 14 Dec 2011 12:59:59 EST http://www.sciencedaily.com/releases/2011/12/111214125906.htm http://www.sciencedaily.com/releases/2011/12/111206151448.htm A UCSF study suggests patients with chronic pain may experience greater relief if their doctors add cannabinoids – the main ingredient in cannabis or medical marijuana – to an opiates-only treatment. The findings, from a small-scale study, also suggest that a combined therapy could result in reduced opiate dosages. Tue, 06 Dec 2011 15:14:14 EST http://www.sciencedaily.com/releases/2011/12/111206151448.htm http://www.sciencedaily.com/releases/2011/11/111121142501.htm Researchers have discovered a new means of enhancing the effects of anandamide -- a natural, marijuana-like chemical in the body that provides pain relief. Mon, 21 Nov 2011 14:25:25 EST http://www.sciencedaily.com/releases/2011/11/111121142501.htm http://www.sciencedaily.com/releases/2011/11/111114221018.htm A high childhood IQ may be linked to subsequent illegal drug use, particularly among women, new research suggests. Mon, 14 Nov 2011 22:10:10 EST http://www.sciencedaily.com/releases/2011/11/111114221018.htm http://www.sciencedaily.com/releases/2011/11/111102161047.htm Researchers studied whether legalizing medical marijuana in Rhode Island would be likely to increase its use among youths. Based on their analysis of 32,570 students, they found that while marijuana use was common throughout the study period, there were no statistically significant differences in marijuana use between states where medical marijuana was legal and where it was illegal in any year. Wed, 02 Nov 2011 16:10:10 EDT http://www.sciencedaily.com/releases/2011/11/111102161047.htm http://www.sciencedaily.com/releases/2011/10/111031115226.htm A new report suggests that deficits in endocannabinoid function may contribute to anorexia nervosa and bulimia. Endocannabinoids are substances made by the brain that affect brain function and chemistry in ways that resemble the effects of cannabis derivatives, including marijuana and hashish. These commonly abused drugs are well known to increase appetite, i.e., to cause the "munchies." Thus, it makes sense that deficits in this brain system would be associated with reduced appetite. Mon, 31 Oct 2011 11:52:52 EDT http://www.sciencedaily.com/releases/2011/10/111031115226.htm http://www.sciencedaily.com/releases/2011/10/111025172633.htm Cannabis use is associated with disturbances in concentration and memory. New research by neuroscientists in the UK has found that brain activity becomes uncoordinated and inaccurate during these altered states of mind, leading to neurophysiological and behavioral impairments reminiscent of those seen in schizophrenia. Tue, 25 Oct 2011 17:26:26 EDT http://www.sciencedaily.com/releases/2011/10/111025172633.htm http://www.sciencedaily.com/releases/2011/10/111020025752.htm Researchers have sequenced the genome of Cannabis sativa, the plant that produces both industrial hemp and marijuana, and in the process revealed the genetic changes that led to the plant's drug-producing properties. Thu, 20 Oct 2011 02:57:57 EDT http://www.sciencedaily.com/releases/2011/10/111020025752.htm http://www.sciencedaily.com/releases/2011/10/111020024443.htm Throughout history, Cannabis sativa has been exploited by humanity. Hemp seed oil is rich in omega 6, and its fiber is used in the production of fabrics. Marijuana is known for its mind-altering properties. The changes to the genome that led to drug-producing plants is a mystery of cannabis evolution, but one that has now been solved, thanks to new research. Thu, 20 Oct 2011 02:44:44 EDT http://www.sciencedaily.com/releases/2011/10/111020024443.htm http://www.sciencedaily.com/releases/2011/10/111010074853.htm Young people who are genetically vulnerable to depression should be extra careful about using cannabis: smoking cannabis leads to an increased risk of developing depressive symptoms, according to a new study carried out by researchers in the Netherlands. Two-thirds of the population have the gene variant that makes one sensitive to depression. Mon, 10 Oct 2011 07:48:48 EDT http://www.sciencedaily.com/releases/2011/10/111010074853.htm http://www.sciencedaily.com/releases/2011/10/111006173453.htm Researchers have found that drivers who test positive for marijuana or report driving within three hours of marijuana use are more than twice as likely as other drivers to be involved in motor vehicle crashes. The researchers also found evidence that crash risk increases with the concentration of marijuana-produced compounds in the urine and the frequency of self-reported marijuana use. Thu, 06 Oct 2011 17:34:34 EDT http://www.sciencedaily.com/releases/2011/10/111006173453.htm http://www.sciencedaily.com/releases/2011/10/111006125418.htm A chemical component of the marijuana plant could prevent the onset of pain associated with drugs used in chemotherapy, particularly in breast cancer patients. Thu, 06 Oct 2011 12:54:54 EDT http://www.sciencedaily.com/releases/2011/10/111006125418.htm http://www.sciencedaily.com/releases/2011/09/110923095016.htm A Spanish study on the consumption of drugs amongst university students confirms that non-prescribed drug abuse amongst those who use cannabis, tobacco and alcohol could be considered "another form of multi-drug consumption." Fri, 23 Sep 2011 09:50:50 EDT http://www.sciencedaily.com/releases/2011/09/110923095016.htm http://www.sciencedaily.com/releases/2011/09/110922152629.htm A new research study recommends a public health approach to cannabis -- including evidence-based guidelines for lower-risk use -- to reduce the health harms that result from the use of cannabis. Thu, 22 Sep 2011 15:26:26 EDT http://www.sciencedaily.com/releases/2011/09/110922152629.htm http://www.sciencedaily.com/releases/2011/09/110921120037.htm Administration of cannabinoids (in the form of synthetic marijuana) after experiencing a traumatic event blocks the development of post-traumatic stress disorder-like symptoms in rats, according to a rat study conducted by researchers in Israel. Wed, 21 Sep 2011 12:00:00 EDT http://www.sciencedaily.com/releases/2011/09/110921120037.htm http://www.sciencedaily.com/releases/2011/08/110830213619.htm Scientists report the development of much needed new tests to help cope with a wave of deaths, emergency room visits and other problems from a new genre of dangerous designer drugs sold legally in stores and online that mimic the effects of cocaine, ecstasy and marijuana. Tue, 30 Aug 2011 21:36:36 EDT http://www.sciencedaily.com/releases/2011/08/110830213619.htm http://www.sciencedaily.com/releases/2011/07/110712093856.htm Researchers have discovered a mechanism that seems to protect the brain from aging. In experiments with mice, they switched off the cannabinoid-1 receptor. As a consequence, the animals showed signs of degeneration -- as seen in people with dementia -- much faster. Tue, 12 Jul 2011 09:38:38 EDT http://www.sciencedaily.com/releases/2011/07/110712093856.htm http://www.sciencedaily.com/releases/2011/07/110711104926.htm College athletes tend to be less likely than their non-athlete peers to smoke marijuana. But when they do, they may have some different reasons for it, according to a new study. Mon, 11 Jul 2011 10:49:49 EDT http://www.sciencedaily.com/releases/2011/07/110711104926.htm http://www.sciencedaily.com/releases/2011/06/110627095647.htm Researchers found that a brief, voluntary conversation with an adult led to up to a 20 percent decrease in marijuana use for teenagers who frequently used the drug. Mon, 27 Jun 2011 09:56:56 EDT http://www.sciencedaily.com/releases/2011/06/110627095647.htm http://www.sciencedaily.com/releases/2011/06/110623085953.htm It's well known that drunk driving can have fatal consequences, but a new study suggests that alcohol is not the only drug that's a danger on the road. Researchers found that of US drivers who died in a crash, about 25 percent tested positive for drugs. The most common drugs were marijuana and stimulants, including cocaine and amphetamines. Thu, 23 Jun 2011 08:59:59 EDT http://www.sciencedaily.com/releases/2011/06/110623085953.htm http://www.sciencedaily.com/releases/2011/06/110606131705.htm Definitive proof of an adverse effect of chronic marijuana use could lead to potential drug treatments and aid other research involved in cannabinoid receptors, a neurotransmission system receiving a lot of attention. Mon, 06 Jun 2011 13:17:17 EDT http://www.sciencedaily.com/releases/2011/06/110606131705.htm http://www.sciencedaily.com/releases/2011/05/110509122718.htm Aboriginal-youth living off-reserve in Canada use tobacco, alcohol and drugs significantly more than non-Aboriginal youth and have higher health risks, according to a new article. Mon, 09 May 2011 12:27:27 EDT http://www.sciencedaily.com/releases/2011/05/110509122718.htm http://www.sciencedaily.com/releases/2011/04/110405174833.htm Drugs like marijuana act on naturally occurring receptors in the brain called cannabinoid receptors. However, the mechanisms by which these drugs produce their sensory and mood altering effects within the brain are largely unknown. Researchers have now identified a critical brain pathway responsible for the effects of cannabinoid drugs on how the brain processes emotional information. Tue, 05 Apr 2011 17:48:48 EDT http://www.sciencedaily.com/releases/2011/04/110405174833.htm http://www.sciencedaily.com/releases/2011/03/110328161840.htm Any possible pain relief that marijuana has for people with multiple sclerosis may be outweighed by the drug's apparent negative effect on thinking skills, according to new research. Mon, 28 Mar 2011 16:18:18 EDT http://www.sciencedaily.com/releases/2011/03/110328161840.htm http://www.sciencedaily.com/releases/2011/03/110305102545.htm Researchers are studying heavy users of marijuana to help understand what exercise does for the brain, contributing to a field of research that uses exercise as a modality for prevention and treatment. Participants saw a significant decrease in their cravings and daily use after just a few sessions of running on the treadmill, according to a new study. Sat, 05 Mar 2011 10:25:25 EST http://www.sciencedaily.com/releases/2011/03/110305102545.htm http://www.sciencedaily.com/releases/2011/03/110301184056.htm Cannabis use during adolescence and young adulthood increases the risk of psychotic symptoms, while continued cannabis use may increase the risk for psychotic disorder in later life, concludes a new study. Tue, 01 Mar 2011 18:40:40 EST http://www.sciencedaily.com/releases/2011/03/110301184056.htm http://www.sciencedaily.com/releases/2011/02/110222192830.htm The active ingredient in cannabis can improve the appetites and sense of taste in cancer patients, according to a new study. Tue, 22 Feb 2011 19:28:28 EST http://www.sciencedaily.com/releases/2011/02/110222192830.htm http://www.sciencedaily.com/releases/2011/02/110222122212.htm New evidence suggests that cannabis may have an even greater negative effect on sexual health than previously thought. Tue, 22 Feb 2011 12:22:22 EST http://www.sciencedaily.com/releases/2011/02/110222122212.htm http://www.sciencedaily.com/releases/2011/02/110222122208.htm The federal anti-drug campaign "Above the Influence" appears to have effectively reduced marijuana use by teenagers, new research shows. A study of more than 3,000 students in 20 communities nationwide found that by the end of 8th grade, 12 percent of those who had not reported having seen the campaign took up marijuana use compared to only 8 percent among students who had reported familiarity with the campaign. Tue, 22 Feb 2011 12:22:22 EST http://www.sciencedaily.com/releases/2011/02/110222122208.htm http://www.sciencedaily.com/releases/2011/02/110207165434.htm Cannabis use appears to be associated with an earlier onset of psychotic illness, according to a meta-analysis of previously published studies. Mon, 07 Feb 2011 16:54:54 EST http://www.sciencedaily.com/releases/2011/02/110207165434.htm http://www.sciencedaily.com/releases/2010/11/101124214728.htm Immunologists studying the effects of cannabis have discovered how smoking marijuana can trigger a suppression of the body's immune functions. The research reveals why cannabis users are more susceptible to certain types of cancers and infections. Wed, 24 Nov 2010 21:47:47 EST http://www.sciencedaily.com/releases/2010/11/101124214728.htm http://www.sciencedaily.com/releases/2010/11/101117121809.htm Researchers have discovered differences in the development of the amygdala region of the brain -- which is critical to the expression of emotional and social behaviors -- in animal models that may help to explain why some mental health disorders are more prevalent among boys. They also found a surprising variable -- a difference between males and females in the level of endocannabinoid, a natural substance in the brain that affected their behavior, specifically how they played. Wed, 17 Nov 2010 12:18:18 EST http://www.sciencedaily.com/releases/2010/11/101117121809.htm http://www.sciencedaily.com/releases/2010/11/101116104202.htm New research shows that people who start using marijuana at a young age and those who use the greatest amount of marijuana may be the most cognitively impaired. Tue, 16 Nov 2010 10:42:42 EST http://www.sciencedaily.com/releases/2010/11/101116104202.htm http://www.sciencedaily.com/releases/2010/09/100929083516.htm In a new study, researchers report evidence of an association between father's incarceration and substantially elevated risks for illegal drug use in adolescence and early adulthood. Wed, 29 Sep 2010 08:35:35 EDT http://www.sciencedaily.com/releases/2010/09/100929083516.htm http://www.sciencedaily.com/releases/2010/09/100920131140.htm American and Italian researchers have found that a novel drug allows anandamide -- a marijuana-like chemical in the body -- to effectively control pain at the site of an injury. Mon, 20 Sep 2010 13:11:11 EDT http://www.sciencedaily.com/releases/2010/09/100920131140.htm http://www.sciencedaily.com/releases/2010/09/100902073633.htm Health professionals have a responsibility to respect and support patients who use cannabis for medicinal purposes, but must stay within the law and follow professional guidance at all times. UK researchers studied more than 50 published papers, together with professional and Government guidance documents, official reports and media coverage, from 1996 to 2009. Their findings highlight the legal, ethical and medical dilemmas faced by the healthcare profession when patients use cannabis for medical reasons. Thu, 02 Sep 2010 07:36:36 EDT http://www.sciencedaily.com/releases/2010/09/100902073633.htm http://www.sciencedaily.com/releases/2010/09/100902073507.htm New research shows that the "gateway effect" of marijuana -- that teenagers who use marijuana are more likely to move on to harder illicit drugs as young adults -- may be overblown. Thu, 02 Sep 2010 07:35:35 EDT http://www.sciencedaily.com/releases/2010/09/100902073507.htm http://www.sciencedaily.com/releases/2010/09/100901072901.htm Hispanic middle school students may be more likely to smoke, drink or use marijuana than their peers of other races and ethnicities, whereas Asian students seem to have the lowest risk, according to new research. Wed, 01 Sep 2010 07:29:29 EDT http://www.sciencedaily.com/releases/2010/09/100901072901.htm http://www.sciencedaily.com/releases/2010/08/100830094926.htm The medicinal use of cannabis has been debated by clinicians, researchers, legislators and the public at large for many years as an alternative to standard pharmaceutical treatments for pain, which may not always be effective and may have unwanted side effects. A new study provides evidence that cannabis may offer relief to patients suffering from chronic neuropathic pain. Mon, 30 Aug 2010 09:49:49 EDT http://www.sciencedaily.com/releases/2010/08/100830094926.htm http://www.sciencedaily.com/releases/2010/08/100824151036.htm Repeatedly boosting brain levels of one natural painkiller soon shuts down the brain cell receptors that respond to it, so that the painkilling effect is lost, according to a surprising new study that has important implications for drug development. Tue, 24 Aug 2010 15:10:10 EDT http://www.sciencedaily.com/releases/2010/08/100824151036.htm http://www.sciencedaily.com/releases/2010/08/100806161857.htm A newly discovered molecular mechanism helps control the amount and effectiveness of a substance that mimics an active ingredient in marijuana, but that is produced by the body's own nerve cells. Cannabinoid signaling systems are common throughout the body and affect a variety of functions. Developing new therapies that modulate these molecular communications might help patients with autoimmune or neurological disorders, including brain inflammation following a viral infections. Specifically targeted treatments would have medicinal benefits without mind-altering side effects. Fri, 06 Aug 2010 16:18:18 EDT http://www.sciencedaily.com/releases/2010/08/100806161857.htm http://www.sciencedaily.com/releases/2010/07/100707222548.htm A new compound similar to the active component of marijuana (cannabis) might provide effective pain relief without the mental and physical side effects of cannabis, according to a new study. Wed, 07 Jul 2010 22:25:25 EDT http://www.sciencedaily.com/releases/2010/07/100707222548.htm http://www.sciencedaily.com/releases/2010/03/100319202524.htm Recent studies have shown that behaviors such as happiness, obesity, smoking and altruism are "contagious" within adult social networks. In other words, your behavior not only influences your friends, but also their friends and so on. Researchers have taken this a step farther and found that the spread of one behavior in social networks influences the spread of another behavior -- adolescent drug use. Fri, 19 Mar 2010 20:25:25 EDT http://www.sciencedaily.com/releases/2010/03/100319202524.htm http://www.sciencedaily.com/releases/2010/03/100303092405.htm In the last month, a professor of toxicology at Saint Louis University has seen nearly 30 cases involving teenagers who were experiencing hallucinations, severe agitation, elevated heart rate and blood pressure, vomiting and, in some cases, tremors and seizures. All of these teens had smoked a dangerous, yet legal substance known as K2 or "fake weed." Wed, 03 Mar 2010 09:24:24 EST http://www.sciencedaily.com/releases/2010/03/100303092405.htm http://www.sciencedaily.com/releases/2010/03/100301165726.htm Young adults who have used cannabis or marijuana for a longer period of time appear more likely to have hallucinations or delusions or to meet criteria for psychosis, according to a new study. Mon, 01 Mar 2010 16:57:57 EST http://www.sciencedaily.com/releases/2010/03/100301165726.htm http://www.sciencedaily.com/releases/2010/02/100217152331.htm Researchers in California have found "reasonable evidence that cannabis is a promising treatment" for some specific, pain-related medical conditions. Wed, 17 Feb 2010 15:23:23 EST http://www.sciencedaily.com/releases/2010/02/100217152331.htm http://www.sciencedaily.com/releases/2010/02/100208091926.htm The benefits of marijuana in tempering or reversing the effects of Alzheimer's disease have been challenged in a new study. Mon, 08 Feb 2010 09:19:19 EST http://www.sciencedaily.com/releases/2010/02/100208091926.htm http://www.sciencedaily.com/releases/2009/12/091222121809.htm Teens who frequently listen to music that contains references to marijuana are more likely to use the drug than their counterparts with less exposure to such lyrics, according to a new study. Tue, 22 Dec 2009 12:18:18 EST http://www.sciencedaily.com/releases/2009/12/091222121809.htm http://www.sciencedaily.com/releases/2009/12/091220144936.htm Progression to daily marijuana use in adolescence may hasten the onset of symptoms leading up to psychosis, a new study finds. Sun, 20 Dec 2009 14:49:49 EST http://www.sciencedaily.com/releases/2009/12/091220144936.htm http://www.sciencedaily.com/releases/2009/12/091219073005.htm Marijuana is the most commonly used illicit drug in the United States. Roughly eight to 12 percent of marijuana users are considered "dependent" and, just like alcohol, the severity of symptoms increases with heavier use. A new study has found that use and misuse of alcohol and marijuana are influenced by a common set of genes. Sat, 19 Dec 2009 07:30:30 EST http://www.sciencedaily.com/releases/2009/12/091219073005.htm http://www.sciencedaily.com/releases/2009/12/091217115834.htm The damaging effects of the illicit drug Cannabis on young brains are worse than originally thought, according to a psychiatric researcher. A new study suggests that daily consumption of cannabis in teens can cause depression and anxiety, and have an irreversible long-term effect on the brain. Thu, 17 Dec 2009 11:58:58 EST http://www.sciencedaily.com/releases/2009/12/091217115834.htm http://www.sciencedaily.com/releases/2009/12/091203222136.htm Cannabis can reduce spasticity in multiple sclerosis patients. A systematic review found that five out six randomized controlled trials reported a reduction in spasticity and an improvement in mobility. Thu, 03 Dec 2009 22:21:21 EST http://www.sciencedaily.com/releases/2009/12/091203222136.htm http://www.sciencedaily.com/releases/2009/11/091130192917.htm Substituting cannabis in place of more harmful drugs may be a winning strategy in the fight against substance misuse. New research features a poll of 350 cannabis users, finding that 40 percent used cannabis to control their alcohol cravings, 66 percent as a replacement for prescription drugs and 26 percent for other, more potent, illegal drugs. Mon, 30 Nov 2009 19:29:29 EST http://www.sciencedaily.com/releases/2009/11/091130192917.htm http://www.sciencedaily.com/releases/2009/11/091116143623.htm Marijuana is the most widely used illicit drug by adolescents, with almost 42 percent of high school seniors admitting to having experimented with it. Many studies have focused on parents as being the best avenue for preventing adolescent marijuana use; however, the strength of the relationship between monitoring and marijuana usage has been unclear. According to a meta-analysis, there is in a fact a strong, reliable link between parental monitoring and decreased marijuana usage in adolescents. Mon, 16 Nov 2009 14:36:36 EST http://www.sciencedaily.com/releases/2009/11/091116143623.htm http://www.sciencedaily.com/releases/2009/11/091104091726.htm Use of cannabinoids (marijuana) could assist in the treatment of post-traumatic stress disorder patients, according to a new study. Wed, 04 Nov 2009 09:17:17 EST http://www.sciencedaily.com/releases/2009/11/091104091726.htm http://www.sciencedaily.com/releases/2009/10/091022101538.htm Last year the UK government reclassified cannabis from a class C to a class B drug, partly out of concerns that cannabis, especially the more potent varieties, may increase the risk of schizophrenia in young people. But the evidence for the relationship between cannabis and schizophrenia or psychosis remains controversial. A new study has determined that it may be necessary to stop thousands of cannabis users in order to prevent a single case of schizophrenia. Thu, 22 Oct 2009 10:15:15 EDT http://www.sciencedaily.com/releases/2009/10/091022101538.htm http://www.sciencedaily.com/releases/2009/09/090930132702.htm New research looks at the specific ways parents and peers influence teenagers to smoke, drink and use marijuana in combination. Wed, 30 Sep 2009 13:27:27 EDT http://www.sciencedaily.com/releases/2009/09/090930132702.htm