home
RSS
Marijuana nearly doubles risk of collisions
February 9th, 2012
06:30 PM ET

Marijuana nearly doubles risk of collisions

We hear a lot about the hazards of drunk driving, but here's something else to put on your radar: A study in the British Medical Journal found that marijuana nearly doubles the risk of vehicle collisions.

Researchers conducted a systematic review of nine studies on the subject of marijuana and driving accidents, which incorporated almost 50,000 participants.

Alcohol impairs drivers' speed and reaction time, while cannabis affects spatial location, said Mark Asbridge, associate professor in the Department of Community Health and Epidemiology at Dalhousie University in Halifax, Nova Scotia.

Among impaired drivers, fatally injured drivers, and motor vehicle crash victims, marijuana is the most prevalent illegal drug that has been detected, according to the U.S. National Institute on Drug Abuse.

Drivers who have recently smoked marijuana may follow cars too closely, and swerve in and out of lanes, Asbridge said.

People who are impaired by alcohol often recognize that they're impaired by alcohol, but "people under the influence of cannabis often deny feeling impaired in any way," Asbridge noted.

It's not unusual for young people to go to a party and give the "designated driver" responsibility to the person who uses marijuana, Asbridge said.

"There clearly is a lot of misconception about the extent to which cannabis impairs performance," he said. "People just don't believe it."

As with alcohol, cannabis has different effects on different people. People metabolize cannabis in different ways.  Some inhale more than others.

The effects of cannabis tend to wear off within three to four hours, whereas alcohol can mess your thinking up longer. Depending on how much you drank, you may not be able to drive for up to 12 hours after you finish drinking.

If the driver is 35 or younger, there's a higher likelihood of marijuana consumption leading to collisions, previous research has found.

There's not enough information known about the effects of marijuana doses on collisions - in other words, what level of cannabis in a person's system correlates most with crashes.

And Asbridge's conclusions are based on observational studies, meaning there were no controlled conditions imposed to look at the effects of marijuana.

One problem in some of the existing research is that there was no measurement of cannabis within two to three hours of driving. Inactive metabolites of THC, a chemical found in marijuana,  can be present in urine for weeks or even a month after usage; marijuana usage so long ago would not affect driving performance or collisions. So Asbridge's group looked only at studies where there was a recent measurement. They also looked at studies that looked at both drivers who used marijuana and those who did not to compare the collision rate.

To deter marijuana usage just before driving, there is roadside testing for cannabis in Australia, western Europe and the United States, Wayne Hall of the University of Queensland in Australia said in an accompanying editorial.

Hall called for further research to evaluating the impact of roadside drug testing on preventing driver deaths connected to vehicle accidents and cannabis use.


soundoff (1,501 Responses)
  1. Leadership Words

    Way cool! Some very valid points! I appreciate you penning this article and also the rest of the site is extremely good.

    https://i.w55c.net/ping_match.gif?rurl=https://backboneleaders.com/

    June 27, 2021 at 03:29 | Report abuse | Reply
  2. Types Of Leadership Styles

    http://www.uktrademarkregistration.co.uk/JumpTo.aspx?url=https://backboneleaders.com

    June 27, 2021 at 04:58 | Report abuse | Reply
  3. podcast hosting sites

    https://lb.affilae.com/r/?p=5ce4f2a2b6302009e29d84f3&af=6&lp=http://backbonehunters.com

    June 27, 2021 at 05:38 | Report abuse | Reply
  4. Leadership Behaviors

    Everything is very open with a really clear description of the issues. It was truly informative. Your site is very helpful. Many thanks for sharing!

    http://www.nbsmedia.ru/bitrix/rk.php?goto=https://backboneleaders.comholostyak-stb-2021

    June 27, 2021 at 06:06 | Report abuse | Reply
  5. Leadership

    Hello, I do think your website may be having web browser compatibility issues. When I look at your web site in Safari, it looks fine but when opening in IE, it has some overlapping issues. I just wanted to provide you with a quick heads up! Apart from that, wonderful blog!

    https://www.priyo.com/feed/redirection?url=https://backboneleaders.com/

    June 27, 2021 at 08:56 | Report abuse | Reply
  6. Brian Houston Leadership Podcast

    Good write-up. I absolutely appreciate this website. Keep it up!

    http://flash.wakunavi.net/rank.cgi?mode=link&id=333&url=https://backboneleaders.com

    June 27, 2021 at 09:04 | Report abuse | Reply
  7. Leadership Academy

    Iím impressed, I have to admit. Seldom do I come across a blog thatís equally educative and amusing, and let me tell you, you have hit the nail on the head. The problem is something which not enough men and women are speaking intelligently about. I'm very happy I stumbled across this during my search for something relating to this.

    http://bbs.cfish.idv.tw/link.php?url=http://backboneleaders.com/

    June 27, 2021 at 09:41 | Report abuse | Reply
  8. morning joe podcast

    Very nice article. I certainly love this site. Keep it up!

    https://rosreestr.gov.ru/bitrix/redirect.php?event1=&event2=&event3=&goto=https://www.backbonehunters.com

    June 27, 2021 at 12:16 | Report abuse | Reply
  9. Great Man Theory Of Leadership

    I enjoy reading through an article that will make people think. Also, many thanks for allowing for me to comment!

    https://community.rsa.com/external-link.jspa?url=https://backboneleaders.com/

    June 27, 2021 at 12:25 | Report abuse | Reply
  10. Strengths Based Leadership

    http://nudewwedivas.forumcommunity.net/m/ext.php?url=http://backboneleaders.com

    June 27, 2021 at 13:17 | Report abuse | Reply
  11. RV Repair Seal Beach

    Hi there! This article couldnít be written any better! Going through this article reminds me of my previous roommate! He constantly kept preaching about this. I will send this post to him. Pretty sure he'll have a very good read. Many thanks for sharing!

    http://dwarsliggerdelen.net/__media__/js/netsoltrademark.php?d=ocrv.fun

    June 27, 2021 at 16:17 | Report abuse | Reply
  12. Mercedes Luxury Van Repair

    http://oidhreacht.ie/webpilot/translate/lang.asp?url=https://www.commercialvanrepairshop.com

    June 27, 2021 at 17:32 | Report abuse | Reply
  13. RV Repair San Clemente California

    http://www.hyipzone.net/goto.php?url=https://ocrvmotorsports.biz/

    June 27, 2021 at 20:07 | Report abuse | Reply
  14. pharmacepticacom

    hydroxychlor 200 mg https://pharmaceptica.com/

    June 27, 2021 at 20:12 | Report abuse | Reply
  15. Ford Cargo Van Repair Shop

    Your style is very unique compared to other people I've read stuff from. Many thanks for posting when you have the opportunity, Guess I'll just bookmark this site.

    http://mf10.jp/cgi-local/click_counter/click3.cgi?cnt=frontown1&url=http://fleetautorepairshop.com/

    June 28, 2021 at 01:13 | Report abuse | Reply
  16. Sprinter Van Maintenance Shop Near Me

    http://www.drachenzaehmenleichtgemacht.at/notice.php?url=https://commercialrepairshop.com

    June 28, 2021 at 04:29 | Report abuse | Reply
  17. Camper Repair Shops Near Me

    Itís difficult to find knowledgeable people about this subject, however, you sound like you know what youíre talking about! Thanks

    http://www.egyup.com/__media__/js/netsoltrademark.php?d=ocrv.tv

    June 28, 2021 at 04:38 | Report abuse | Reply
  18. RV Repair Shops Near Me Now

    An intriguing discussion is worth comment. I think that you should publish more about this subject matter, it may not be a taboo matter but usually folks don't discuss these issues. To the next! All the best!!

    http://www.sports-ranking.com/search/rank.cgi?mode=link&id=7&url=https://ocrvmotorsports.net

    June 28, 2021 at 08:03 | Report abuse | Reply
  19. RV Repair Shops Near My Location

    Good write-up. I certainly love this website. Thanks!

    http://environmentalriskadvisory.com/__media__/js/netsoltrademark.php?d=ocrvmotorcoaches.com

    June 28, 2021 at 10:13 | Report abuse | Reply
  20. Sprinter Repair Costa Mesa

    Everything is very open with a clear clarification of the challenges. It was definitely informative. Your website is extremely helpful. Many thanks for sharing!

    https://www.fairpoint.net/~jensen1242/gbook/go.php?url=ocrvcenter.com

    June 28, 2021 at 10:42 | Report abuse | Reply
  21. Mercedes Camper Van Repair Shop

    http://thaythuoccuaban.com/weblink1.php?web_link_to=ocrvcenter.com/

    June 28, 2021 at 10:51 | Report abuse | Reply
  22. RV Repair Near Me

    Spot on with this write-up, I seriously feel this website needs far more attention. Iíll probably be back again to read more, thanks for the advice!

    http://www2.golflink.com.au/out.aspx?frm=gglcmicrosite&target=https://newrvowners.com

    June 28, 2021 at 18:51 | Report abuse | Reply
  23. Approved Sprinter Repair Shops Near Me

    I couldnít refrain from commenting. Very well written!

    http://bartdesmet.net/utility/Redirect.aspx?U=http://ocrvmotorcoachsales.com

    June 28, 2021 at 21:28 | Report abuse | Reply
  24. RV Repair Seal Beach

    http://focus.pulseresearch.com/homeseller/redirect.html?hs_site_id=113&hs_id=146&redirect=http://ocrv.online/

    June 29, 2021 at 00:59 | Report abuse | Reply
  25. RV Repair Near Me Now

    https://www.esavo.fi/campaigns/marklink?id=583eb2abe4b0dd6cf816167f&link=http://www.ocrvpaintandservice.com&email=vesa.huttunen@esavo.fi

    June 29, 2021 at 04:44 | Report abuse | Reply
  26. Ford High Top Van Repair Shop Near Me

    An intriguing discussion is worth comment. I believe that you should publish more on this subject matter, it may not be a taboo matter but usually folks don't discuss such subjects. To the next! Best wishes!!

    http://www.info-az.net/search/rank.cgi?mode=link&id=675&url=http://www.ocrvmotorcoaches.com

    June 29, 2021 at 11:20 | Report abuse | Reply
  27. Nearby RV Repair

    Good day! I could have sworn Iíve visited this site before but after looking at some of the posts I realized itís new to me. Anyways, Iím definitely happy I found it and Iíll be bookmarking it and checking back regularly!

    http://www.monitor.uxp.ru/forum/out.php?https://newrvowners.com

    June 29, 2021 at 13:49 | Report abuse | Reply
  28. RV Repair Santa Ana

    Hello, I do believe your website might be having internet browser compatibility problems. When I take a look at your site in Safari, it looks fine but when opening in IE, it has some overlapping issues. I merely wanted to provide you with a quick heads up! Aside from that, great site!

    http://www.svaboda.org.2.gsr.anonimizing.com/home287/createSession?referer=https://www.ocrvcenter.com

    June 29, 2021 at 14:54 | Report abuse | Reply
  29. RV Repair Shops Near Me Now

    Iím amazed, I must say. Seldom do I come across a blog thatís equally educative and engaging, and without a doubt, you've hit the nail on the head. The problem is something that too few folks are speaking intelligently about. I'm very happy that I found this during my search for something regarding this.

    http://act.stopcorporateabuse.org/salsa/track.jsp?key=-1&url_num=4&url=https://www.ocrvcenter.com

    June 29, 2021 at 16:52 | Report abuse | Reply
  30. best cbd gummies

    I am so grateful for your article post.Really thank you! Really Cool.

    https://bit.ly/3x2ZiGJ

    June 29, 2021 at 19:13 | Report abuse | Reply
  31. Sprinter Repair Orange County

    http://car.pchome.com.tw/api/ad_click.php?url=http://ocrv.guru

    June 29, 2021 at 19:27 | Report abuse | Reply
  32. Sprinter Resistor Repair

    http://www.mchammer.com/__media__/js/netsoltrademark.php?d=ocrvfleetservices.com/

    June 29, 2021 at 22:07 | Report abuse | Reply
  33. RV Repair Near Me

    The very next time I read a blog, I hope that it does not fail me as much as this particular one. I mean, Yes, it was my choice to read through, but I actually believed you would have something helpful to talk about. All I hear is a bunch of crying about something you can fix if you were not too busy looking for attention.

    http://mrshabanali.com/?wptouch_switch=desktop&redirect=https://ocrvmotorcoaches.com

    June 30, 2021 at 02:40 | Report abuse | Reply
  34. Credit Counseling orlando

    best i have ever seen!Hello, always i used to check webpage posts here early in the daylight, for the reason that i love to gain knowledge of more and more.

    https://goo.gl/maps/z5QxDM4xnvD2

    June 30, 2021 at 05:15 | Report abuse | Reply
  35. orlando credit repai

    A great read. I'll definitely be back.

    https://goo.gl/maps/WTPBHu1Md2N2

    June 30, 2021 at 05:38 | Report abuse | Reply
  36. Commercial Locksmith Cave Creek

    such a great information for blogger i am a professional blogger thanks

    https://www.google.com/maps?cid=106407147833378062

    June 30, 2021 at 06:02 | Report abuse | Reply
  37. Auto Insurance Englewood CO

    very nice! Ireally like your blog

    https://www.google.com/maps?cid=12039124596540498887

    June 30, 2021 at 06:28 | Report abuse | Reply
  38. hvac repairs near fayetteville nc

    Thanks for wonderful information I used to be in search of this info for my mission.

    https://beeah-uae.com/hvac-repair-information-you-need/

    June 30, 2021 at 06:49 | Report abuse | Reply
  39. Camper Repairs Near Me

    There's definately a lot to know about this topic. I really like all the points you've made.

    http://local.ksby.com/__media__/js/netsoltrademark.php?d=ocrvexperts.com

    June 30, 2021 at 07:00 | Report abuse | Reply
  40. Heater Repair Fayetteville NC

    Interesting stuff to read. Keep it up.

    https://dryconknox.com/how-to-choose-the-ideal-hvac-repair-service/

    June 30, 2021 at 07:09 | Report abuse | Reply
  41. raleigh body shops

    A great read. I'll definitely be back.

    https://www.thecreativeallianceexperience.com/keep-money-in-to-your-pocket-with-auto-body-repairs/

    June 30, 2021 at 07:38 | Report abuse | Reply
  42. body shop raleigh nc

    such a great information for blogger i am a professional blogger thanks

    https://www.momstressrelief.com/keep-money-in-to-your-pocket-with-auto-body-repairs/

    June 30, 2021 at 08:00 | Report abuse | Reply
  43. estate planning Spokane

    Really very happy to say,your post is very interesting to read.I never stop myself to say something about it.You're doing a great job.Keep it up

    https://www.google.com/maps?cid=11933253185015063857

    June 30, 2021 at 08:40 | Report abuse | Reply
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Leave a Reply to Leadership Academy


 

CNN welcomes a lively and courteous discussion as long as you follow the Rules of Conduct set forth in our Terms of Service. Comments are not pre-screened before they post. You agree that anything you post may be used, along with your name and profile picture, in accordance with our Privacy Policy and the license you have granted pursuant to our Terms of Service.

Advertisement
About this blog

Get a behind-the-scenes look at the latest stories from CNN Chief Medical Correspondent, Dr. Sanjay Gupta, Senior Medical Correspondent Elizabeth Cohen and the CNN Medical Unit producers. They'll share news and views on health and medical trends - info that will help you take better care of yourself and the people you love.