Tags Effects


Are there risks from secondhand marijuana smoke? Early science says yes

3/19/18--Scientists are finding that, just as with secondhand smoke from tobacco, inhaling secondhand smoke from marijuana can make it harder for arteries to expand to allow a healthy flow of blood. Read

Stronger cannabis linked to rise in demand for drug treatment programmes

1/31/18--Study drawing on data from the Netherlands is the first to show how admissions to treatment centres rise and fall in line with cannabis strength. Furthermore, it found that changes in demand for treatment typically lagged five to seven years behind changes to cannabis strength. Read

Cannabis use is associated with reduced prevalence of progressive stages of alcoholic liver disease

1/17/18--A study revealed that among alcohol users, individuals who additionally use cannabis (dependent and non‐dependent cannabis use) showed significantly lower odds of developing alcoholic steatosis (AS), steatohepatitis (AH), fibrosis, cirrhosis (AC) and hepatocellular carcinoma (HCC). Additionally, findings suggest that cannabis use is associated with a reduced incidence of liver disease in alcoholics. Read

Cigarettes and pot linked to teen psychosis

1/19/18--For teens, using either marijuana or cigarettes is associated with higher odds of psychotic-like experiences, a new study published Wednesday in the journal JAMA Psychiatry found. Psychosis describes the mental condition of losing touch with reality, such as experiencing hallucinations or delusions. Read

More women smoking marijuana while pregnant, U.S. study finds

12/26/17--A growing number of pregnant women are using marijuana, and the habit is expanding fastest among teens and young adults, a U.S. study suggests. Among teen mothers under age 18, marijuana use during pregnancy surged from about 13 percent in 2009 to almost 22 percent in 2016, researchers found. Over that same period, the proportion of pregnant women aged 18 to 24 using marijuana rose from 10 percent to 19 percent. Across all age groups, marijuana use during pregnancy increased from 4 percent at the start of the study to 7 percent by the end. Read

Pueblo doctors see rise in marijuana sickness cases

12/11/17--Emergency room doctors at St. Mary-Corwin Medical Center in Pueblo are seeing a rise of illnesses due to an excessive intake of marijuana. It's a condition called scromiting, commonly referred as Cannabinoid Hyperemesis Syndrome, which results in symptoms like screaming and vomiting. Medical experts believe the symptoms are the result of people consuming heavy amounts of marijuana over extended periods of time. Read  

Marijuana use may not aid patients in opioid addiction treatment

12/4/17--Many patients who are being treated for opioid addiction in a medication-assisted treatment clinic use marijuana to help manage their pain and mood symptoms. But, new research led by Marian Wilson, Ph.D., of the Washington State University College of Nursing found that frequent marijuana use seems to strengthen the relationship between pain and depression and anxiety, not ease it. Read

Rates and predictors of conversion to schizophrenia or bipolar disorder following substance-induced psychosis

11/28/17--The authors investigated the rates of conversion to schizophrenia and bipolar disorder after a substance-induced psychosis, as well as risk factors for conversion. The study concludes that substance-induced psychosis is strongly associated with the development of severe mental illness, and a long follow-up period is needed to identify the majority of cases. Read

Rare and mysterious vomiting illness linked to heavy marijuana use

11/30/17--Cannabinoid hyperemesis syndrome, a condition only recently acknowledged by the medical community, affects a small population — namely, a subset of marijuana users who smoke multiple times a day for months, years or even decades. Doctors say it's difficult to treat the condition. There is no cure other than to quit using marijuana. Furthermore, doctors can do little to relieve the symptoms, since traditional anti-nausea medications often don't work and there are no pills to prevent the onset of an episode. Read

Vomiting syndrome discovered in some long-term marijuana users

11/30/17--Long-term and very heavy marijuana use may cause severe stomach pain and vomiting in a very small percentage of users, according to local San Diego researchers. County and health officials say Cannabinoid Hyperemesis Syndrome (CHS) causes symptoms ranging from severe stomach pain, nausea, vomiting, and the impulse to take hot showers. The condition is linked to long-term, heavy marijuana use and causes abdominal discomfort that may mimic other intestinal illnesses. Read

Cannabis use in youth is linked to bipolar symptoms in young adults, finds new research

11/30/17--Researchers from Warwick Medical School found that adolescent cannabis use is an independent risk factor for future hypomania -- periods of elated mood, over-active and excited behaviour, and reduced need for sleep that are often experienced as part of bipolar disorder, and have a significant impact on day-to-day life. The Warwick research is the first to test the prospective association between adolescent cannabis use and hypomania in early adulthood, whilst controlling for important other factors that might explain this connection. Read

Using cannabis just twice a week as a teenager increases the risk of bipolar disorder in later life

12/1/17--Teenage cannabis use may increases a person's risk of suffering from bipolar disorder in later life, new research suggests. People who used cannabis at least two-to-three times a week at 17 years old are more likely to experience hypomania in their earlier 20s, according to the first study of its kind. Read

Research finds link between marijuana use and testicular cancer

11/8/17--New research from Northern Medical Program Professor Dr. Russ Callaghan has found that use of marijuana is associated with the development of testicular cancer. As part of a retrospective study, Dr. Callaghan and his team looked at data from young men conscripted for military service in Sweden in 1969 and 1970, and tracked their health conditions over the following 42 years. They found that heavy cannabis use (defined as more than 50 times in a lifetime, as measured at conscription) was associated with a 2.5-fold increased risk of developing testicular cancer. Read

Cannabis use and incidence of testicular cancer

11/1/17--Given current drug policy reforms to decriminalize or legalize cannabis in numerous countries worldwide, the current study assesses the relation between cannabis use and the development of testicular cancer. Read

Marijuana and alcohol negatively impact lifetime achievement in young adults

10/31/17--UConn Health examined the effects of marijuana use and dependence on life achievement in young adults. Research found that young adults dependent on marijuana and alcohol were less likely to achieve adult life goals, defined by the study as educational achievement, full-time employment, marriage, and social economic potential. Research also revealed that dependence may have a more severe effect on young men. Read

Teens who drank or smoked marijuana heavily are less likely to marry, go to college, or work full time

11/5/17--Young adults dependent on marijuana and alcohol are less likely to achieve adult life goals, according to new research by UConn Health scientists. They examined data from the Collaborative Study on the Genetics of Alcoholism (COGA) to track the effect teenage alcohol and marijuana use has on the achievement of life goals, defined as educational achievement, full time employment, marriage, and social economic potential. The researchers also found that dependence may have a more severe effect on young men. Read

Medical marijuana won’t help most sick kids

10/23/17--A new review suggests that medical marijuana appears to hold only limited promise for sick children and teenagers, and according to study author Dr. Shane Shucheng Wong there's not enough evidence to say that medical marijuana can specifically help kids with medical conditions, such as neuropathic pain, post-traumatic stress disorder (PTSD), or Tourette's syndrome. Even though there seem to be some good uses for medical pot, doctors and families need to weigh potential negative effects in treating children and teens with marijuana, Wong noted. Read

Marijuana can help children with seizures, cancer nausea

10/23/17--According to a new study published in the journal Pediatrics, medical marijuana is effective in treating seizures and chemotherapy-induced nausea in young patients. Researchers conducted a meta-analysis, looking at 22 relevant studies on the use of medical cannabis on children and adolescents to reach this conclusion. Some advocates have hailed these results as further proof of the effectiveness of medical marijuana, particularly in cases where children haven’t responded to other traditional treatments. Read

Why dangerously potent pot is making people lose their minds and memories

10/19/17--A new study, published by Manchester Metropolitan University in the U.K., reports high-potency pot is causing psychiatric issues, including addiction and memory problems. New strains of the recreational drug have higher levels of the active chemical and not enough of another compound that keeps the drug safe. Apparently, the riskiest pot is coming from the black market, which could be an argument for expanding legalization. Read

Cannabis consumption increases violent behavior in young people in psychiatric care

10/6/17--A new study on cannabis use that involved 1,136 patients (from 18 to 40 years of age) with mental illnesses who had been seen five times during the year after discharge from a psychiatric hospital demonstrates that sustained used of cannabis is associated with an increase in violent behavior in young people. Moreover, the association between persistent cannabis use and violence is stronger than that associated with alcohol or cocaine. Read

Smoking cannabis DOES make people more violent

10/4/17--Cannabis users are more likely to commit violent crime, pioneering research has shown. It warned those who smoke the drug regularly run an increased risk of using violence against others. The project is the first to demonstrate that cannabis is not only linked with violent crime but is the cause. Read

Common marijuana-related cases encountered in the emergency department

10/1/17--As the number of people using marijuana has increased, there has been a parallel increase in marijuana-related emergency department (ED) visits and poison center calls. It is expected that as other states liberalize marijuana laws, they will also experience an increase in marijuana-related ED visits. This article reviews several common marijuana-related ED cases that have existed in the medical profession. Read

Cancer-causing compounds found in cannabis oil

9/27/17--A recent study from investigators at Portland State University found benzene and other potentially cancer-causing chemicals in the vapor produced by butane hash oil, a cannabis extract. Findings from the new study—published recently in ACS Omega in an article entitled “Toxicant Formation in Dabbing: The Terpene Story”—raises health concerns about dabbing, or vaporizing hash oil—a practice that is growing in popularity, especially in states that have legalized medical or recreational marijuana. Read

Cannabis use and risk of prescription opioid use disorder in the United States

9/26/17--Mark Olfson, M.D., M.P.H., Melanie M. Wall, Ph.D., Shang-Min Liu, M.S., and Carlos Blanco, M.D., Ph.D. sought to determine whether cannabis use is associated with a change in the risk of incident nonmedical prescription opioid use and opioid use disorder at 3-year follow-up. The study concluded that cannabis use appears to increase rather than decrease the risk of developing nonmedical prescription opioid use and opioid use disorder. Read

Up to one-quarter of cancer patients use marijuana

9/25/17--A new study conducted in a cancer center in a state with legalized medicinal and recreational marijuana found that approximately one-quarter of surveyed patients used marijuana in the past year, mostly for physical and psychological symptoms. Published early online in CANCER, a peer-reviewed journal of the American Cancer Society, the study also revealed that legalization increased the likelihood for use among patients. Read

Confusion lingers over health-related pros and cons of marijuana

9/20/17--In 29 states and in Washington, D.C., marijuana is now commonly prescribed for post-traumatic stress disorder and chronic pain. But the drug’s pros and cons remain hazy. Regular pot use has been linked to psychotic disorders and to alcohol and drug addiction, and two recent research reviews conclude that very little high-quality data exist on whether marijuana effectively treats PTSD or pain. Several large-scale trials are under way to assess how well cannabis treats these conditions. Read

Cannabis, ‘spice’ – better think twice

9/21/17--A research group discovered that seizures can be induced by natural Δ9-tetrahydrocannabinol (Δ9-THC, main constituent of marijuana) or the synthetic cannabinoid JWH-018 (main component of synthetic blend "Spice"). These results are considered important because people see marijuana as a soft drug, without dangerous health effects, and they are unaware of the particularly severe effect of those cannabinoids. Considering the recent irreversible spread of synthetic cannabinoids and their impact on human health, this data should serve as a public alert. Read

Marijuana may produce psychotic-like effects in high-risk individuals

9/13/17--Marijuana may bring on temporary paranoia and other psychosis-related effects in individuals at high risk of developing a psychotic disorder, finds a preliminary study from researchers at Columbia University Medical Center (CUMC). In this double-blinded, placebo-controlled laboratory study, the researchers looked at the effects of marijuana in six high-risk young adults and six controls, all experienced and current marijuana smokers who were physically healthy. Read

Marijuana with ‘CBD’ may pose less risk to long-term users

9/8/17--According to a new study authored by Dr. Ken Mackie, a professor in the Department of Psychological and Brain Sciences at Indiana University, marijuana with relatively high levels of cannabidiol may be less risky to smoke over the long term, because this ingredient may counteract some of the drug's harmful effects. Read

Smoking a couple of joints a week? Research warns it may make sperm ‘more mellow’ and swim in circles

8/31/17--Recent research indicates that smoking too much marijuana can cause sperm to become “more mellow and swimming in circles,” resulting in lower sperm counts by almost a third. According to Dr. Victor Chow, a clinical associate professor at the University of British Columbia Medical School’s department of urological sciences, the effect on male fertility is strong because “sperm is a very rapidly turning over cell." Heavy marijuana use can have an immediate effect on sperm production because the male body makes new sperm about every three months. Read

Marijuana laced with Fentanyl hits Tennessee

8/24/17--Tennessee District Attorney Matthew Stowe said that the state is seeing an influx of a deadly mixture: marijuana and fentanyl. Officials in the state are preparing to respond to this new trend as marijuana laced with fentanyl hits Tennessee. Fentanyl is an especially potent—and dangerous—opioid pain medication. It is used in a variety of prescription painkillers and can be highly addictive. Beyond that, it can easily lead to fatal overdoses. Read

Medical expert reports on marijuana problems in Colorado

8/14/17--Libby Stuyt, MD, an addictions psychiatrist, medical director at the Colorado State Hospital in Pueblo, and president of the National Acupuncture Detoxification Association, has a unique and expert view on the effect of increased marijuana availability and use. Stuyt’s data is from information collected by the state of Colorado and from her experience as a clinician and researcher. Read

UMass Med School specialist helps doctors learn about marijuana’s risks, benefits

8/17/17--Dr. Ehrlich, clinical associate professor of family medicine and community health at University of Massachusetts Medical School, was one of the reviewers of a new Comprehensive Cannabis Curriculum, developed by the Massachusetts Medical Society together with Harvard Medical School-affiliated Dr. Stephen B. Corn and Dr. Meredith Fisher-Corn. The curriculum is intended to equip doctors and health care providers with robust training on the medical, legal, and social issues regarding marijuana use. According to Dr. Ehrlich, physicians need to have access to better information to discuss both the therapeutic uses as well as the adverse effects of marijuana with their patients.

The Effects of Cannabis Among Adults With Chronic Pain and an Overview of General Harms

9/5/17--A systematic review examines the benefits of plant-based cannabis preparations for treating chronic pain in adults, and the harms of cannabis use in chronic pain and general adult populations. Limited evidence suggests that cannabis may alleviate neuropathic pain in some patients, but insufficient evidence exists for other types of chronic pain. Among general populations, limited evidence suggests that cannabis is associated with an increased risk for adverse mental health effects. Read

Marijuana may help ease nerve pain, review finds

8/15/17--Marijuana may be slightly effective at reducing chronic nerve pain known as neuropathy. But there's little evidence on whether or not pot helps treat other types of pain or post-traumatic stress disorder (PTSD), a pair of new studies suggests. Read

Marijuana use holds three-fold blood pressure death risk: study

8/9/17--According to scientists, people who smoke marijuana have a three times greater risk of dying from hypertension, or high blood pressure, than those who have never used the drug. The risk grows with every year of use, they said. The findings, from a study of some 1,200 people, could have implications in the United States among other countries. Read

Marijuana associated with three-fold risk of death from hypertension

8/9/17--Marijuana use is associated with a three-fold risk of death from hypertension, according to new research. Compared to non-users, marijuana users had a 3.42-times higher risk of death from hypertension, and a 1.04 greater risk for each year of use. There was no association between marijuana use and death from heart disease or cerebrovascular disease. Read

Marijuana ‘may be worse than cigarettes for cardiovascular health’

8/9/17--People who use marijuana may be three times more likely to die from high blood pressure than non-users of the drug, a new study finds. The researchers say that their findings indicate that marijuana use is a greater risk factor for poor cardiovascular health than cigarette smoking. Read

Unusual marijuana-related illness grabbing attention of Boston doctors

7/27/17--Dr. Michael Donnino of Beth Israel Deaconess Medical Center is launching what would become one of the nation's first case studies into Cannabinoid Hyperemesis Syndrome or CHS - a syndrome caused by excessive marijuana use. Dr. Donnino says a lack of research and knowledge stumped doctors who didn't realize they were looking at cases of CHS for many years. Read

Pattern of marijuana use during adolescence may impact psychosocial outcomes in adulthood

7/25/17--A pattern of escalating marijuana use in adolescents is linked to higher rates of depression and lower educational accomplishments in adulthood. Those findings come from a new study led by researchers from the Department of Psychiatry at the University of Pittsburgh School of Medicine and Pitt Department of Psychology published in the journal Addiction. Read

These college students lost access to legal pot — and started getting better grades

7/25/17--The most rigorous study yet of the effects of marijuana legalization has found that college students with access to recreational cannabis on average earn worse grades and fail classes at a higher rate. The research on more than 4,000 students, published in the Review of Economic Studies, found that those who lost access to legal marijuana showed substantial improvement in their grades. Specifically, those banned from cannabis cafes had a more than 5 percent increase in their odds of passing their courses. Read

Marijuana and the opioid epidemic: separating fact from fiction

6/27/17--Despite national headlines claiming that states with legal marijuana have lower opioid overdose rates, NIDA reports that there is insufficient evidence to confirm that legalizing marijuana will reduce opioid use and overdose deaths. NIDA is funding additional studies to determine the link between medical marijuana use and the use or misuse of opioids for pain. Read

Machine measures smoking impact

7/6/17--Leslie Sutherland, a research scientist with the Health Sciences North Research Institute, is using a large contraption referred to as Borg, the smoking machine, to examine the dangers of smoking – tobacco and marijuana. Sutherland says she believes she is the first researcher to look into the effects of cannabis smoke from this perspective. Her study centres on the earliest changes that occur at the cellular level, once the cells have been exposed to smoke. Read

Marijuana and vulnerability to psychosis

7/5/17--Going from an occasional user of marijuana to a weekly or daily user increases an adolescent's risk of having recurrent psychotic-like experiences by 159%, according to a new Canadian study published in theJournal of Child Psychology and Psychiatry. The study also reports effects of marijuana use on cognitive development and shows that the link between marijuana use and psychotic-like experiences is best explained by emerging symptoms of depression. Read

School Of Public Health study finds use of marijuana increases risk of metabolic syndrome

6/29/17--According to a recent study by researchers in the School of Public Health at Georgia State University, the duration of marijuana use seems to be a significant factor associated with metabolic syndrome -- a cluster of symptoms that increase a person’s risk for heart disease, stroke, and diabetes. The study found that “every year increase in marijuana use is associated with at least a 5 percent increase in odds of having metabolic syndrome.” Read

Losing train of thought or it’s hard to multi-task? You may be having one drink too many

6/20/17--Impairments using information that help with decision-making and planning simple tasks are linked with one's frequency of alcohol or drug use. A new study shows that cognitive impairments constitute a broader problem among substance users in the US general population. This is the first study to find associations between deficits in attention with frequency of binge drinking and use of marijuana, cocaine, opioids, tranquilizers, and stimulants in the general population ages 18 and older. Read

Stoner barf: Yes, it’s a thing, and it’s way more common than you think

6/19/17--Health experts say marijuana may be making people sick. Emergency medicine physicians at UC Davis Medical Center said they’ve seen young, often college-age patients, come in once or twice a day vomiting multiple times an hour and screaming uncontrollably. The condition is known as cannabinoid hyperemesis syndrome, or CHS, and doctors believe it’s caused when cannabinoids in marijuana bombard neurotransmitters, causing an imbalance in the body’s regulatory system. Read

One in 5 adolescents at risk of tobacco dependency, harmful alcohol consumption, and illicit drug use

6/10/17--Researchers from the University of Bristol have found regular and occasional cannabis use as a teen is associated with a greater risk of other illicit drug taking in early adulthood. The study by Bristol's Population Health Science Institute, published online in the Journal of Epidemiology & Community Health, also found cannabis use was associated with harmful drinking and smoking. Read

Marijuana use during pregnancy associated with many risks, studies reveal

6/7/17--Many mothers turn to marijuana for relief of symptoms such as nausea and anxiety, yet scientific research is emerging that identifies associated risks. Using marijuana can affect a person's ability to safely care for a baby or other children. Marijuana use also decreases a person's ability to concentrate, impairs judgment, and slows response time. Read

Quebec psychiatrists urge strict guidelines for marijuana bill

6/5/17--The Quebec Association of Psychiatric Physicians argues that based on their clinical experience, the bill to legalize marijuana is not acceptable in its current form, and will expose young people to major mental health risks. According to the doctors’ opinions, authorizing the purchase of marijuana at 21 instead of 18 years old would allow a better balance to be struck between reducing the harms caused by the illicit market and protecting future generations. Read

Low-dose THC can relieve stress; more does just the opposite

6/2/17--Researchers at the University of Illinois at Chicago and the University of Chicago report that low levels tetrahydrocannabinol, or THC, the main psychoactive compound in marijuana, does reduce stress, but in a highly dose-dependent manner: very low doses lessened the jitters of a public-speaking task, while slightly higher doses actually increased anxiety. Read

Cannabis use increases risk of gum disease

5/25/17--Researchers have linked the use of cannabis to an increase in the risk of gum disease. A new study from Columbia University shows that the frequent use of marijuana, hashish, and hash oil has significant long-term impacts on dental health. Read

DEA chief: ‘Marijuana is not medicine’

5/25/17--Drug Enforcement Administration acting Chief Chuck Rosenberg remains strong on his stance that "marijuana is not medicine." Despite repeated attempts by advocates requesting that marijuana be moved to Schedule II, the DEA has pointed to the FDA's guidance that says it does not have medical value. Rosenberg noted that the DEA takes recommendations about how to classify the drug from the FDA. Read

Science Says: What’s known and not known about marijuana

5/29/17--A new marijuana study joins a limited record of scientific knowledge about the harms and benefits of pot. In January, a U.S. advisory committee concluded that the lack of scientific information about marijuana and its chemical cousins, called cannabinoids, poses a risk to public health. The experts called for a national effort to learn more. In a report from the National Academies of Sciences, Engineering and Medicine, they also rounded up what is known, and outline some of its conclusions with strong evidence about marijuana and cannabinoids. Read

Trying new marijuana products and edibles is associated with unexpected highs

5/15/17--A new study by RTI International suggests that unexpected highs are a consequence of using new marijuana products and edibles -- products that have flooded the marijuana market since legalization of recreational marijuana use. Read

Marijuana use tied to poorer school performance

5/11/17--According to a new study from the University of Waterloo, when high school students started smoking marijuana regularly they were less likely to get good grades and want to pursue college. The study, published in the Journal of School Health, found that when students started using marijuana at least once a month they were about four times more likely to skip class, two-to-four times less likely to complete their homework and value getting good grades, and about half as likely to achieve high grades, than when they had never used the drug. Read

36 million Americans are allergic to marijuana – causing asthma, inflammation and rashes

5/12/17--More than 36 million Americans could be allergic to marijuana, figures show. According to a report on the nation's allergies, 73 percent of the 50 million people who react to pollen also have issues with cannabis - and the figure is rising. Scientists found in some cases exposure to marijuana pollen or cannabis smoke provoked symptoms of allergic rhinitis, caused by inflammation of the nasal passages, causing sneezing, congestion, itching, and a runny nose. They also found symptoms of conjunctivitis and asthma. Read

Marijuana use during pregnancy may affect child’s vision

5/7/17--A recent study finds that exposure to marijuana in the womb may affect the development of the offspring’s eye. These changes were found to persist as mice in this particular experiment aged. The scientists exposed pregnant mice to either marijuana or filtered air throughout their gestation. When their eyes were inspected, the mice whose mothers had been exposed to marijuana had significantly thinner retinas than those exposed to filtered air. Little is known about cannabis and its impact on retinal development, so this study is likely to pave the way for more in-depth research. Read

Gestational exposure to marijuana smoke may have lasting effects on the retina

5/8/17--Scientists have shown for the first time that gestational exposure to marijuana smoke in animals affects the development of the eye and these alterations seem to progress with age. Read

ER visits related to marijuana use at a Colorado hospital quadruple after legalization

5/4/17--Visits by teens to a Colorado children's hospital emergency department and its satellite urgent care centers increased rapidly after legalization of marijuana for commercialized medical and recreational use, according to new research being presented at the 2017 Pediatric Academic Societies Meeting in San Francisco. Read