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Is Marijuana Addictive?

The age old question is still being debated today.


Marijuana. Addictive or no? That question has been batted back and forth for decades. While many, especially regular users, say, "Absolutely not!" others are convinced that the answer is a resounding "Yes!" So which is it? Marijuana is a political hot button, thus much research has concentrated on the addictive properties of this plant.

The vast majority of those who use marijuana do so occasionally and exhibit no addictive symptoms — no increased tolerance, no cravings and no withdrawal. In other words, they can take it or leave it.

According to NIDA, marijuana is the most commonly abused illicit drug in the U.S. Why? It’s accessible, affordable, and not considered harmful. In addition, more and more state legislatures are legalizing medicinal marijuana. Presently, 16 states and DC have legalized medical marijuana, and 12 states have pending legislation. Fourteen states have decriminalized marijuana, and cities and counties within certain states have followed suit. California and a few other places have removed almost all penalties for possession.

According to AlterNet, 41 percent of Americans, or 102 million people, have tried marijuana at least once in their lifetime; 10 percent or 26 million Americans have used marijuana in the past year, and 6 percent, or 15 million Americans, admit to using marijuana on a ‘regular’ basis. It is estimated that around 10 percent of those who smoke marijuana on a regular basis become long term, chronic users.


Some history: Delta-9-tetrahydrocannabinol, or THC, is the main active chemical in marijuana. When smoked, THC quickly passes through the lungs and into the bloodstream, thus carrying it to various organs -- including the brain – where the bulk of cannabinoid receptors reside. These receptors were discovered in the 1980's, and there are two known types, CB1 and CB2, but it’s suspected there are more. These receptors mediate the high via a variety of complex mechanisms.

They are not just limited to man, animals have them, too — mammals, fish, reptiles and birds. They have an effect on coordinated movement, thinking, memory, pleasure and time perception. CB1 is found in very high levels in many regions of the brain; CB2 receptors are found in many of the immune cells, as well as neurons.

While marijuana's effects are felt within minutes, it peaks in about half an hour. It's not just a relaxed dreamy state and the munchies that constitute the high, which is what users crave — but it also has many physiological effects like dry mouth, increased heart rate, impaired coordination, delayed reaction time and slowed memory and concentration. Some smokers even experience paranoia and hallucinations. Although the effects usually wear off within three hours, THC accumulates in the fatty tissue of the liver, lungs, testes and other organs.

Urine tests can indicate the presence of marijuana for two weeks or longer for an occasional smoker. The length of time marijuana remains in the body depends not only how often a person smokes but also on how long he has been smoking. Individuals who are daily smokers can test positive 45 days after use, and heavy daily smokers can test positive 90 days after last use.


According to the Alcohol Drug Abuse Help & Resource Center, there is a fine line between use and abuse with respect to a psychoactive drug. Look no further than alcohol and try to come up with a definition that will delineate the two. Abuse can be defined as use that leads to significant problems in life related to: problems with work/school, use in dangerous situations (driving a car), substance-related legal problems, or continued substance use that interferes with friendships and/or family relationships. Of course, all of these are part of the definition of addiction as well.

We know anything can be abused, even water, and no one argues that marijuana can be abused. The question is whether it can be addicting as well. Which of course in the end will come down to our definition of addiction, which is why this remains controversial.

Also controversial is whether chronic use of the drug causes brain damage. There are studies that say emphatically yes, as in a new Australian study, which claims changes occur in regions of the brain, overall structure or metabolism. This study compared long term heavy use to brain damage that is equal to a mildly traumatic brain injury. But then again there are other studies, like one from the Medicinal Cannabis Research Center, which found only minor differences from the control group, not only in regards to structure and metabolism but also with respect to intelligence testing, memory and concentration.

As for physical effects, according to The Washington Post, a study reported at the American Thoracic Society International Conference found no connection between marijuana and lung cancer — even with regular and heavy marijuana smokers. This is stunning, when you consider that this is a drug that is typically smoked.

As expected, marijuana use can have an effect on driving, although not as severe (and for a shorter time frame) as alcohol. According to ADAI, while studies show that being under the influence of marijuana can cause some perception and reaction problems, many will consciously alter their driving to compensate for their decreased reaction time by driving slower and keeping a larger distance behind the car ahead. But, this compensation doesn't help if something unexpected happens and most experts at least agree on one thing with respect to marijuana: driving while high is grounds for a DUI.


DSM-IV describes drug dependence as the compulsive regular use of a substance, despite ONGOING negative consequences. Addiction symptoms include all of those listed above for abuse, plus tolerance (the need for a higher dose to get the same effect), withdrawal symptoms (when the drug is stopped) and cravings.

Some drugs are very physically and psychologically addictive and have obvious, terrible withdrawal symptoms. These are easy to identify, such as heroin, barbiturates or alcohol. Others like marijuana are psychologically addictive, and the withdrawal includes psychological symptoms like anxiety, mood swings and depression. These are harder to identify, leading to the question of whether they are really related to withdrawal versus a “I miss my pot” phenomenon.

So what does it take for someone to be addicted? Is it the shakes, the sweats, and the vomiting like the junkie coming off opiates? Most folks have this image of severe symptoms— physical addiction -- as being uncontrollable. Yet the psychological addiction of marijuana is seen as less severe and hence manageable, needing only a good dose of willpower to get over it. But, the psychological craving can be stronger than the physical withdrawal. The brain wants what it wants, when it wants it and for some these cravings are overwhelming.

In other words the brain craves the drug of choice despite the negative consequences involved. Whether the addict loses his job, savings, home or family, the brain relentlessly continues to crave the drug and the user will continue to use, all the while justifying and rationalizing why he does not have a problem. After all, denial is a huge part of any addiction. It’s just a bit easier to deny with pot than with other “more dangerous” drugs.

If you acknowledge that psychological withdrawal symptoms consitiute withdrawal, then there is no doubt that marijuana meets all of the criteria to be considered addicting.


In the end there is clearly developing proof that marijuana is addicting, and clinically there are numerous reports. From my website alone, I have received dozens of stories, regarding addiction to THC. Citing just a few: Marilynn Asks How To Help Her Pot-Addict Husband, Will My Marriage Be The Casualty Of His Marijuana Smoking Habit?, Alisha's Husband Puts Pot Before Her And The Babies, Margaret Can No Longer Watch Her Son Destroy Himself, Natalia Assumed Her Husband Would Outgrow Pot, KLM's Brother Smokes Pot 24/7, My Husband Chooses Marijuana Over Me and My Husband Smokes Marijuana Morning, Noon and Nigh.

These letters come from distraught spouses, lovers, fiancés, friends and parents, not the marijuana user himself. Is he even aware his marriage is on the rocks? Does he know he has anger issues? Does he get why he was fired from work? The letters illustrate that regardless of what you want to call it, marijuana can wreck marriages, families, careers and lives.

The bottom line is this: As with everything, moderation is key. Anything can be abused, and everything should be respected. If you have become dependent on marijuana and have tried to stop but failed, even with the threat of going to jail or losing your family, friends or career then yes, I think it's safe to say you have an addiction.

Just like alcohol, some folks can smoke marijuana with little downside. It's those who start to use marijuana as a crutch, who find they must have a hit to get through the day, who cannot go a length of time without getting high, no matter what the costs.... that's when it becomes clear there's a problem. If you are having an issue with family, friends or career, and others believe that marijuana is the cause and you want to prove them wrong, there is an easy way. I tell my patients to stop smoking, completely, for six months. If you can do that, then you are probably okay. If you can't, or won’t, then guess what? You are probably addicted.

It's just a matter of time before marijuana is legalized. As more and more states put fewer and fewer restrictions on marijuana, eventually it will be legal to smoke, eat, sell and even cultivate. So, should we fight the legalization of this addictive drug? Of course not.

Chronic alcohol use causes many known physical problems, clearly defined brain damage, more auto-related fatalities and disrupts more families and careers then marijuana does, by far.It simply means that users will need to take charge of the amount and frequency of their use of this controversial drug, just like they should do with alcohol, saturated fats and sugar. That's not such a bad thing — it's called personal responsibility.

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