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What's New in Marijuana Research

Marijuana Intoxication

Posted: March 1st, 2012 by MJ Research Blog

Recently there has been an increase in emergency room visits for marijuana intoxication, perhaps due to the recently stronger potency of marijuana.  The most common symptoms of intoxication are euphoria, misperception of time, sedation, disturbed perceptions, continuous giggling, red eyes, increased heart rate, dry mouth and increased appetite.  Death from intoxication is very rare.  Also, some users have anxiety, panic attacks and hallucinations, both with high and normal doses of marijuana.

A recent article (Harm Reduction Jl 9:7, 2012) reviewed use of medications to reduce intoxication.  Propanolol, a medication used to treat cardiac conditions reduced several symptoms in well-done studies.  Sometimes medications designed to block marijuana effects (rimonabant),  reduce anxiety (benzodiazepines) or reduce hallucinations (antipsychotics) are used.  These have not been adequately tested in scientific studies.  Thus, currently, most physicians prefer to not use any medications; however, this article suggests use of propanolol should be considered.

Read the full article by downloading the OpenAccess PDF, here

–Dr. John Hughes

We’re Now On Facebook!

Posted: January 19th, 2012 by MJ Research Blog

Loyal readers,

 

We now have a presence on the foremost social network, Facebook.

Here is a link to our Facebook Page, if you find what you’ve been reading here useful and informative, please give us a like! Don’t hesitate to spread the word either. Thanks.

 

Respectfully yours,

MJ Research Blog

New Study on Marijuana and Automobile Accidents

Posted: January 19th, 2012 by MJ Research Blog

Marijuana use worsens reaction time, perception, coordination and decision making; thus, one would think it would worsen driving.  Marijuana appears to influence automatic performance whereas alcohol appears to impair judgment.  Also, some data suggest that marijuana users are more aware of their intoxication than alcohol users and compensate for this by driving slower or more carefully. Moreover, regular users may become tolerant of the intoxicating effects of marijuana. A recent review (Li et al, Epidemiology Reviews 34:65-72, 2012) located nine studies of the risk of automobile crashes.  Eight of the nine studies found more accidents in those using vs. not using marijuana (the one negative study was very small). In these studies, marijuana users were 2.7 times more likely to have an accident. Heavier users of marijuana had more accidents than light users. Use of both alcohol and marijuana together increased accidents even more; however, the effect of marijuana on crashes was not due to their greater use of alcohol.

You can read the full text of the article here

 

–Dr. John R. Hughes

Which Behavioral Strategies Help Marijuana Users Stop?

Posted: December 11th, 2011 by MJ Research Blog

Many marijuana users can easily stop but others cannot do so, despite many attempts.  Past studies found that events such as marriage, a new job, or completing schooling can motivate and help users quit.  Although many clinics, brochures and websites have tips about how to quit, whether these tips really work has rarely been tested.  A recent study (Rooke, Substance Abuse Treatment, Prevention and Policy 6:30, 2011) asked successful and unsuccessful marijuana quitters about 15 different strategies to use when trying to quit.  Successful quitters were those that used coping strategies such as avoiding other marijuana users, finding other ways to relax and anticipating hard times.  Also successful quitters were more likely to have sought out treatment.  Motivational strategies such as thinking about benefits of cessation, removing temptations such as throwing away marijuana in the house and distraction via doing activities instead of using were not effective.

Read the complete study here.

–Dr. John R. Hughes

Marijuana and lung disease

Posted: November 3rd, 2011 by jrhughes

Evolution designed man to avoid, not seek, taking smoke into the lungs; thus, any smoked substance is likely to cause harm.  In fact, marijuana users are more likely to have bronchitis (i.e., coughing and shortness of breath) and lung infections such as pneumonia (Hall W, Lancet 374, p 1383-1391, 2009).  Most, but not all, studies suggest daily marijuana users have impaired lung function. Marijuana smoke includes many of the same cancer-causing chemicals as tobacco smoke and that marijuana use often involvesdeep inhalations; thus, one would think users would have more lung cancer.  Although most studies do suggest marijuana can cause lung cancer, others have not.  This may be because the studies had few participants who used marijuana several times a day.   Many believe that given the logic that marijuana use should cause cancer, we should assume this is so, until proven otherwise.

Read the complete study here

–Dr. John R. Hughes

Marijuana Use and Anxiety

Posted: November 3rd, 2011 by jrhughes

Marijuana has been said to both increase and decrease anxiety or nervousness.  A recent review article (Crippa et al Human Psychopharmacology 24: p 515-523, 2009) clarifies this seeming contradiction.   When scientists find an association between two events (e.g. A and B), then it could mean A causes B, B causes A, or something else else causes both A and B to occur at the same time. The evidence that marijuana causes increased anxiety is limited to two scenarios:  new users of marijuana (i.e. “bad highs”) and high-strength marijuana in regular users.  Often this causes “panic attacks” which include increased heart rate, paranoia, or feeling like one is “losing their mind”, etc.  Most of the evidence indicates marijuana use does not cause a clinically significant anxiety problem.   In fact, marijuana use among regular users appears to decrease anxiety in those who are currently anxious; e.g.  among those giving a speech.  Although THC is the major chemical that causes the subjective effects of marijuana, other similar compounds (called “cannabinoids”) can decrease anxiety as well.  Also, stopping marijuana can cause a withdrawal syndrome that causes anxiety. Anxious persons do appear to be more likely to take up marijuana use and do report it decreases anxiety, although they do not necessarily become less anxious people.  This type of use of marijuana has been called “self-medication.”  Finally, genes, temperament and personality have been thought to both increase anxiety and increase use of marijuana at the same time but the evidence for this is small.

Read about the complete study here

–Dr. John R. Hughes

Can Medications Help Marijuana Users Reduce or Stop?

Posted: November 3rd, 2011 by jrhughes

The difficulty some marijuana users have in reducing or stopping their use appears to be due to a dependence on marijuana; e.g, use of marijuana is to obtain the effects of the drug THC (tetrahydrocannabanol), there are cannabinoid receptors in everyone’s brains, and stopping marijuana can cause a withdrawal symptom.   With other drug dependencies, supplying the active drug in a medication (e.g. using methadone in those with heroin dependence or nicotine replacement in tobacco smokers) has been successful; thus, providing THC via a medication might help marijuana users change.  In fact, a cannabinoid medication (dronabinol or Marinol) has been used for many years to treat pain, nausea, and weight loss in cancer patients.  Also, small studies have found dronabinol decreases marijuana withdrawal symptoms including craving.  Historically, dronabinol has rarely been abused (probably because of its slow onset of action compared to smoked marijuana). Well, someone has finally tested whether dronabinol would help users quit (Levin et al. Drug and Alcohol Dependence 116:142, 2011).  They found that the usual dose of dronabinol reduced withdrawal symptoms but did not increase quitting or reduction in use of marijuana.  The study was well-done with almost all users taking the dronabinol faithfully and urine testing to prevent falsifications.  I can think of only two possible explanations of these negative results: the dose was not high enough and/or they did not study marijuana users who really wanted to change.  Certainly the former explanation, not using a high enough dose, reflects the problem we observed when first testing these types of medications for heroin and nicotine dependence. Of note, the few other medications for marijuana cessation or reduction that have been tested have not looked highly promising.

 

–Dr. John R. Hughes

Marijuana and Cognition

Posted: November 3rd, 2011 by jrhughes

Marijuana use is clearly associated with poorer memory, learning, decision making, impulsivity and attention.  Some have wondered whether these problems are caused by marijuana or predated marijuana use.  A recent review (Crean, Journal of Addictive Medicine 5:1-8, 2011) concluded that marijuana use itself can cause these. It also examined whether these problems persisted after cessation and concluded that most all eventually went away, although sometimes it took several weeks.  The exception was poor impulse control. Thus, it may be that more impulsive people start marijuana and marijuana actually makes them even more impulsive.

 

–Dr. John R. Hughes

What Strategies for Quitting Marijuana Actually Work?

Posted: November 3rd, 2011 by jrhughes

Many self-help websites, publications and helplines list tips to help marijuana users stop smoking.  However, no one has ever scientifically tested if these tips actually work.  One survey asked 65 daily marijuana users who had recently tried to quit on their own, what strategies they used when they tried to quit (Boyd et al American Journal on Addiction 1:35-42, 2005).   The most common ones were: getting rid of my marijuana (28%), stopped going to places where marijuana was smoked (26%), and stopped associating with friends that use marijuana (25%).   None of the strategies were widely used by the majority of those trying to quit.  In addition, only 10%-17% of these users thought these strategies helped them. In fact, none were associated with longer durations of not using when the users tried to quit.  Also, very few reported using any form of treatment to help them stop. Hopefully, future studies will identify which, if any, of these strategies are linked with success.

 

–Dr. John R. Hughes

Marijuana and Driving Accidents

Posted: November 3rd, 2011 by jrhughes

A recent review of the harms from marijuana use (Hall W, Lancet 374, p 1383-1391, 2009) reported that marijuana users are 2-3 times more likely to be in a car accident.  This rate is smaller than that for heavy alcohol drinkers (6-15 times more likely), in part,  because marijuana users appear to be more aware of their impairment and drive slower and take fewer risks. In laboratory studies, the typical doses of marijuana do impair driving ability, especially when long boring driving is involved.

 

–Dr. John R. Hughes

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