Using Marijuana May Not Raise the Risk of Using Harder Drugs (but look at alternative explanation)

RAND's Drug Policy Research Center ^ | December 2, 2002 | RAND's Drug Policy Research Center

[unspun]

Using Marijuana May Not Raise the Risk of Using Harder Drugs

Marijuana is widely regarded as a "gateway" drug, that is, one whose use results in an increased likelihood of using more serious drugs such as cocaine and heroin. This gateway effect is one of the principal reasons cited in defense of laws prohibiting the use or possession of marijuana. A recent analysis by RAND's Drug Policy Research Center (DPRC) suggests that data typically used to support a marijuana gateway effect can be explained as well by a different theory. The new research, by Andrew Morral, associate director of RAND Public Safety and Justice, Daniel McCaffrey, and Susan Paddock, has implications for U.S. marijuana policy. However, decisions about relaxing U.S. marijuana laws must necessarily take into account many other factors in addition to whether or not marijuana is a gateway drug.

Support for the Gateway Effect

Although marijuana has never been shown to have a gateway effect, three drug initiation facts support the notion that marijuana use raises the risk of hard-drug use:

• Marijuana users are many times more likely than nonusers to progress to hard-drug use.

• Almost all who have used both marijuana and hard drugs used marijuana first.

• The greater the frequency of marijuana use, the greater the likelihood of using hard drugs later.

This evidence would appear to make a strong case for a gateway effect. However, another explanation has been suggested: Those who use drugs may have an underlying propensity to do so that is not specific to any one drug. There is some support for such a "common-factor" model in studies of genetic, familial, and environmental factors influencing drug use. The presence of a common propensity could explain why people who use one drug are so much more likely to use another than are people who do not use the first drug. It has also been suggested that marijuana use precedes hard-drug use simply because opportunities to use marijuana come earlier in life than opportunities to use hard drugs. The DPRC analysis offers the first quantitative evidence that these observations can, without resort to a gateway effect, explain the strong observed associations between marijuana and hard-drug initiation.

New Support for Other Explanations

The DPRC research team examined the drug use patterns reported by more than 58,000 U.S. residents between the ages of 12 and 25 who participated in the National Household Surveys on Drug Abuse (NHSDA) conducted between 1982 and 1994.^[1] Using a statistical model, the researchers tested whether the observed patterns of drug use initiation might be expected if drug initiation risks were determined exclusively by

• when youths had a first opportunity to use each drug

• individuals' drug use propensity, which was assumed to be normally distributed^[2] in the population

• chance (or random) factors.

To put it another way, the researchers addressed the question: Could the drug initiation facts listed in the first section of this brief be explained without recourse to a marijuana gateway effect?

Figure 1—Probabilities of Initiating Hard Drugs, Marijuana Users and Nonusers

The research team found that these associations could be explained without any gateway effects:

• The statistical model could explain the increased risk of hard-drug initiation experienced by marijuana users. Indeed, the model predicted that marijuana users would be at even greater risk of drug use progression than the actual NHSDA data show (see Figure 1).

• The model predicted that only a fraction of hard-drug users would not have tried marijuana first. Whereas in the NHSDA data 1.6 percent of adolescents tried hard drugs before marijuana, the model predicted an even stronger sequencing of initiation, with just 1.1 percent trying hard drugs first.

• The modeled relationship between marijuana use frequency and hard-drug initiation could closely match the actual relationship (see Figure 2).

The new DPRC research thus demonstrates that the phenomena supporting claims that marijuana is a gateway drug also support the alternative explanation: that it is not marijuana use but individuals' opportunities and unique propensities to use drugs that determine their risk of initiating hard drugs. The research does not disprove the gateway theory; it merely shows that another explanation is plausible.

Figure 2—Probabilities of Hard-Drug Initiation, Given Marijuana Use Frequency in the Preceding Year

Some might argue that as long as the gateway theory remains a possible explanation, policymakers should play it safe and retain current strictures against marijuana use and possession. That attitude might be a sound one if current marijuana policies were free of costs and harms. But prohibition policies are not cost-free, and their harms are significant: The more than 700,000 marijuana arrests per year in the United States burden individuals, families, neighborhoods, and society as a whole.

Marijuana policies should weigh these harms of prohibition against the harms of increased marijuana availability and use, harms that could include adverse effects on the health, development, education, and cognitive functioning of marijuana users. However, the harms of marijuana use can no longer be viewed as necessarily including an expansion of hard-drug use and its associated harms. This shift in perspective ought to change the overall balance between the harms and benefits of different marijuana policies. Whether it is sufficient to change it decisively is something that the new DPRC research cannot aid in resolving.

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^[1]In subsequent years, respondents have not been asked about their first opportunity to use various drugs.

^[2]That is, some people have a high or low propensity, but most people have a propensity near the middle of the range.

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RB-6010 (2002)

RAND research briefs summarize research that has been more fully documented elsewhere. This research brief describes work done in RAND's Drug Policy Research Center, a joint endeavor of RAND Public Safety and Justice and RAND Health. The research is documented in "Reassessing the Marijuana Gateway Effect" by Andrew R. Morral, Daniel F. McCaffrey, and Susan M. Paddock, Addiction 97:1493-1504, 2002.

Abstracts of RAND documents may be viewed at www.rand.org. Publications are distributed to the trade by NBN. RAND^® is a registered trademark. RAND is a nonprofit institution that helps improve policy and decisionmaking through research and analysis; its publications do not necessarily reflect the opinions or policies of its research sponsors.

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[Hebrews 11:6]

The willingness to break laws is independent of their significance. Either you're law-abiding or you're not.

[Mudboy Slim]

ALL DRUGS ARE BAD!!

ALL DRUGS ARE NOT BAD!!

SomeDrugs are NOT bad, apparently, but who decides?! And who profits from the ongoing WarOnSomeDrugs?!! Terrorists, you say? What about BigBeer?! What about BigLiquor?! And most of all...What about BigGuv'ment?!

The WarOnSomeDrugs is a BigGuv'mentPloy to BoilTheFRog, slooooooowly...MUD

[Mudboy Slim]

"Who profits from the ongoing WarOnSomeDrugs?!! What about BigBeer?! What about BigLiquor?!"

How about the Pharmaceutical Industry?! If marijuana were de-criminalized at the Federal level, then States would begin allowing personal gardens fer personal use...then bartering would become allowable...and eventually Coffee Houses would dot most of America's Cities wherein you could walts right in during the heat of the day, and join yer friends in a quick toke before the dinner buffet...LOL!!

Who loses then?! Yeah, the Terrorists LOSE by not being able to supply an easily-harvestable ContraBand product...but the Federal Leviathan--and States--would not be able to tax the home-grower of cannabis, although the shopowner of the CoffeeHouse would still be liable fer Consumption Taxes, since ALL Federal Income Taxes will be VOLUNTARY!! Also, folks may indeed drink less Beer and Liquor since they've got a FReeBuzz growing in their backyard...don't wanna git in the way of BigBeer and BigLiquor's sky-rocketing profits, do we?!!

PrescientFReegards...MUD

[Mudboy Slim]

"I both speed and litter"

I haven't littered in years...MUD

And I haven't got a speeding ticket since '87!!

[Mudboy Slim]

"Either you're law-abiding or you're not."

BULL$#!+!!...you speak as if you are a SHEEPLE...are ya?!

The Meek SHALL NOT Inherit the Earth, IMHO...MUD

[Don W]

I believe the < Sarcasm > tag was missing.

[TigersEye]

What would happen if we were all just good people?

We wouldn't have to live on planet earth in physical form anymore.

[rb22982]

Based on what research?

Also I'd rather free up 50 billion a year in taxes, return to a 10th amendment country and just prosecute those who commit public intoxication, 'drunk' driving and those who commit violence than uncle bob or teenie tom who smokes marijuana in his house.

[rb22982]

On this site, you never know

[Don W]

You have a point.

[FastCoyote]

"This isn't hard. Anyone willing to try marijuana has already demonstrated the disregard both for the law and for their own wellbeing that might otherwise dissuade them from trying hard drugs. "

I've used marijuana, cocaine, morphine, demerol, valium, Jack Daniels, cigars, oxycodone, aspirin, tylenol, ben gay, vicks vapor rub, Listerine, penicillin, various antibiotics, caffeine, codeine.

And ya know what, I feel just fine, I have zero cravings for any of it and never used more than a smidgen of any of it. My wellbeing has been impaired not one iota, and so I must ask you, what is the point of your paranoia? (by the way, the drugs weere mostly used because of injuries).

[Hermes37]

Republic of Texas,

Thank you for not expressing contempt prior to investigation. You improve the signal to noise ratio here.

In my experience,,, (ALL risk increases on drugs)
At about 7 years old I tried nicotine. (stole parents cigs)
10 years old first drunk. (parents are/were non drinkers)
11 years old smoked first joint. (last day of 5th grade)
12 years old I started 'smokink cigs'. (7th grade)

By age 15 or 16 I had done everything I could get my hands on. When arrested for MJ sale at 17 I had the money for my own bail and fancy lawyer. I didn't continue sales as an adult.

It was not until I was in my late 20's that I tried heroin, and I knew right away it was 'too good' to mess with ever again. Never tried OC or X (except for MDA, but X is "new" MDMA)

I _AM_ a sober alchoholic.
In my life nicotine, alcohol and crack are trouble.
I know of others who can tolerate alcohol without addiction.
I know of few who tolerate nicotine and crack consumption without addiction.
I know of very few 'pot heads' that HAVE to have it.
I am extreemly lucky in that I realized with coca products, I was never gonna get back the sensation of the first smoked hit. I was hooked BEFORE I exhaled the first hit. I had the 'blues' from coke because I couldn't ever get back the sensation of the first time.
It was called 'freebase' back then because it was processed using ether and chemists 'base'. Today coke smokers use baking soda and water to change the PH for smoking purposes.
(I understand they buy it already processed nowadays)

Although I was able to escape coke addiction I remained an active alcoholic for many more years. I even quit smokin pot regularly because it was interfering with my drinking.

Lucky for me I discovered skydiving!!!
I think I started jumpin because I had suicidal tendencies.
When I realized that I could FLY, and that the 'high' from air,altitude, and having your knees in the breeze was better and legal, alcohol started loosing it's luster.
(not it's grip on my sanity)
I swapped freefall for freebase. Safer, better longer high, and legal.
Whilst skydiving I learned that life was OK without CHEMICAL stimulants. (besides adrenaline)
I stopped 'pulling low' 'cause I DIDN'T want to die any more. (ooohhhhh aaaaah did U see THAT!!!!)
Eventually, I reached a bottom alcoholically and did something about it.
Few are as lucky as I am.
I am now also a recovering adrenaline junky, as I haven't been in the air very often for a couple of years.
(1800 jumps, 3 reserve rides, no broken bones)

I have 'rat' friends that think that pot smokin has had no effect on their lives, but they are IGNORANT. (damaged)
One of them even spent 1.5 years in prison and do not think it was a factor. (he had around 100 pounds/plants)
They are 1 issue anti WOD libs.
They highly resemble 1 issue VRWChristian folks.
This is still no reason to have the laws we have regarding pot.
I do know for a fact that I have seen more lives ruined by alcohol than by pot.

I have NEVER seen someone on only pot become _unreasonably_ agressive. With alcohol it is common.
I do not know of any battered children or spouses in pot only households. I know of MANY battered children and spouses from alcohol only families.

I have buried more friends from alcohol related deaths (many) than I have from pot related deaths (none).
A few from skydiving related deaths also!
I do think that people on pot operating motor vehicles do die in crashes, I just do not know of any.
They probably cause some driving too slowly.

The bottom line, they are both dangerous.
The main danger IMneverHO is retarded maturity when consumption begins before adulthood.
I would have probably still become an alcoholic, but I would have matured more beforehand.
Pot was WAY easier to get as a kid in the '70s than alcohol.
It _IS_ because that drugs were not legal that they were easier to obtain. My pot vendor did not have a license to protect.

FYI, now all the pot smokers I know prefer DOMESTIC weed to imported.
What I am saying, is that most are NOT supporting terrorists with their pot usage. (suburban/rural experience only)
They are supporting farmers and for some of you I'm sure 'average' neighbors. Coke is ALL imported. Meth is domestic, but nasty and very dangerous. OxyContin etc. is domestic doctor supported. LSD is likely domestic, but rare.

It is OK with me if alcohol and nicotine users are put through the same shinola that pot users go through.
Smokers are 3/4 of the way there already.
The black market for cigs has skyrocketed since the tax increases. They ARE terrorist types bootlegging cigs.

It's a big part of the sub-culture experience, illegality is.

For those who argue that nicotine is not a drug have never slapped a 21mg patch on before bed and had technicolor dreams as a result. (I only made that mistake once though)
Even the nicotine patch can be ABused.
The only other time I have technicolor dreams is when I have a high fever from the flu. (It's not all bad!)

You might be wondering what an adrenaline junky that rarely jumps anymore does for kicks nowadays.

I like to shred the arguements of long time 'rat' friends by being brutally honest and try to stop 'just' before they loose their restraint and physically harm me for being so Right. I also (sometimes)tell the truth when it is nonPC to do so. (i'm not prefect)
It's counter intuitive not to lie in todays culture, but what a rush!
(It takes work, you gotta think before you answer ANY questions, even simple ones)

I also occasionally post non PC opinions on FR for kicks.
To be invulnerable, you have to be willing to be vulnerable.

All this risk taking in my life has made me fairly good at assesing risk and making decisions based on that risk.
There WAS excellent employment available if you survive long enough. The job market is tougher today though.
Excellent investment opportunities still exist though.
There are benifits for some, they are very rare though.

My 'experience' qualifies me to have an 'informed' opinion.
I loath nothing more than contempt prior to investigation.

Keep in mind, I'm not typical, I suffer from terminal uniqueness. I was never a mean drunk (rare).
I was working full time as a computer tech when my frinds graduated from high school. (I was asked to "quit" HS at 15)
I have been a VP of Technical Services. (small pond)
U.S.Patent# 4926998 is mine!!!
I worked for 8 years for Bell Northern Research/Northern Telecom/Nortel. I was a "Member of Scientific Staff" when I left. (DMS100 switch jockey (OC-12 fiber specialist))
1/2 of my time at Nortel was as a 'functioning alcoholic'
I was never asked to seek treatment or disciplined for substance abuse. (it just quit working for me)
I worked for 3 years as a Network Engineer at 2Com.
(back when it was still 3Com ;-)

--- donning asbestos suit now ---
flame at will, I've been through HELL already, I can cope.

;-)

[Wolfie]

Other countries have decriminalized marijuana.

You don't even have to look that far. 11 States in the U.S. have decriminalized marijuana.

[MrLeRoy]

Looks like unspun forgot to reply to this:

"1) Supply is already everywhere, you won't be increasing supply probably by more than 5-10% upon legalization.
2) The real gateway drugs are alcohol and nicotine. Using this logic is an immediate right to criminalize both of them. Both are far more addictive, kill WAY more people (marijuana is impossible to OD from), and alcohol is much more of an intoxicant."

[MrLeRoy]

A friend of mine tried marijuana once. It made him want to rape and kill

... and become a black jazz musician.

[MrLeRoy]

What would happen if we were all just good people?

"If men were angels, no government would be necessary." -James Madison

But you won't find any support among any of the Founders for the proposition that laws can make people good. So what's your point?

[MrLeRoy]

I'd like to hear HOW everyone became so knowledgeable.

Reading. It's a terrific way to learn about all sorts of things.

[AUgrad]

. and become a black jazz musician

and a bat

[Republic of Texas]

Tell me, by reading, do you know exactly how addictive crack or heroin is?