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Drugs & Health Blog

What’s Wrong With “Medical Marijuana”?

This blog post is archived and is no longer being updated. For the latest content, please visit the main Drugs & Health Blog page.
The NIDA Blog Team

This is the first post of a 3-part series on the science of medical marijuana.  Check out Part 2: Making Medicine From Marijuana, and Part 3: Medicines or Poisons?—Why Cannabinoids Can Both Help and Hurt You.

Before modern medical science, most medicines were raw herbs or herbal concoctions of one sort or another. They sometimes helped patients, but those benefits weren’t very powerful by today’s standards, and they often had a lot of unpredictable or even dangerous side effects.

That’s because all plants contain hundreds or thousands of different chemicals. If you eat or smoke the leaves of any plant, you are putting all those chemicals in your body, and the results can be unpredictable.

Marijuana is no different.

Still, there is growing public support for “medical marijuana,” based on anecdotal evidence (that is, from individual people’s personal experience) that the drug might be useful in treating various diseases, including PTSD (post-traumatic stress disorder), pain, and epilepsy.

Voters in 23 states have now passed laws allowing marijuana to be dispensed to patients, as long as they receive permission from a doctor.

Why doesn’t the Food and Drug Administration (FDA) approve “medical marijuana”?

Turns out, there’s very little scientific evidence that smoking or eating marijuana is effective and safe for treating any medical issues. Scientific evidence would have to come from carefully controlled research studies.

Since there’s no science to back it up, the FDA has not approved smoked or vaporized marijuana for the treatment of any medical condition.

The FDA only approves medicines when large studies examining lots of patients (called clinical trials) show that the medicines work safely. Without these studies, the FDA can’t promise people that the medications will help them and not harm them. 

So why haven’t there been clinical trials on marijuana? 

Because marijuana is a raw herb. There are over 500 different chemicals in marijuana, in combinations that vary widely between different strains and even from plant to plant. This causes serious problems trying to use the whole marijuana leaf, or crude extracts like hash oil, as medicine:

  1. It’s hard to deliver precise, accurate doses of the right chemicals;
  2. It can harm the lungs if users smoke it; and
  3. It causes additional effects—like the “high”—that may interfere with the quality of life of patients taking the drug for serious medical conditions.

Plus, when used by teens or children, it could even harm their brains as they develop.

Today, there are almost no approved medicines that are whole herbs. Although it’s not impossible, it would be very unusual if marijuana became an exception.

How can we discover and use marijuana’s medical benefits without the harms?

In Part 2, you'll learn how scientists are busy trying to create actual medicines from the chemical ingredients in marijuana.

Comments posted to the Drugs & Health Blog are from the general public and may contain inaccurate information. They do not represent the views of NIDA or any other federal government entity.


Refer Madness is alive and well at the NIDA. First the FDA does not approve anything. They review "clinical trials" performed by Big Pharm and stamp them approved. They don't really know anything about a new drug until a couple of years down the road when people start dying from it. Remember every drug ever recalled by the FDA was first proven to be "safe and effective" by the FDA. Since God is the manufacturer of marijuana I guess no one at the FDA believes in him or they don't trust His 1,000's of years of "clinical trials" that have never killed anyone.
Amen to that. God provided us with Marijuana so praise the lord and overgrow America!
God is dead
Just because God poison oak on the earth are you going to rub it all over your body? And based on your theory, if he put cliffs here are you going to jump off of them? And please do tell me, if he put arsenic on the earth are you doing to eat it for the fun of dying? That sure makes a lot of sense.
Your god also supplied Deadly Nightshade to the world, along with Hemlock, Foxglove and a huge variety of dodgy fungi.
Sorry... but you are so childish...all marijuana users are getting sick with the benifit that they are going to receive marijuana for the treatment.......For the "outgrow America!" with the marijuana its going to make the population alot smaller...
It messes up your brain
Please be more specific in the ways and your source of info that it "messes up the brain". With sincere thanks.
i agree
Epilepsy is a neurological condition which causes disturbances to the brain, called seizures. Medical marijuana has proven to not only reduce the frequency of seizures but in some cases cure them from the illness completely. The chemical in the drug which causes the "high" is removed. therefore there are no real negatives. Yes there are cases of side affects, but for somebody suffering hundreds of seizures each day , would you really sacrifice possible the only cure?
It could also help with stress and pain
exacly thats what ive been trying to say, everone trys to find reason marijauana is bad for you but there are no real bad effect of it.
Perhaps it cause you brain damage to the point that you don't know how to write a sentence.
YOU CLAIM marijuna isn't bad but tell me why there are pregnat smokers who give birth to children with defects like if its not that bad why should it hurt you baby .........
Cause it's a baby. Putting something in a baby, let alone a growing fetus is VASTLY different than putting that substance in a grow person, or even a child. There is a lot more important, fragile development going on in those early stages
then dont smoke while your pregnant its as easy as that!!!! even cigarete smokers shouldent smoke when there pregnat but thats legal!!
Read and research the studies by Raphael mechoulam, he is a researcher on THC, canniboid and has specifically studied the benefits of cannibinoids in the medical realm. Do not state mistruths that not enough study has been done. This faloud chemist has studied marijuana since the 1960s and is considered by many to be the leading authority. Instead, ask why the FDA refuses to consider the use of an tau real plant that cannot be patented by big pharma
Use real words not "faloud"(?)
" to me, medical marijuana isnt a big deal. if it helps people, it helps people, not a big deal, but if it hurts you, i would just say be the smart one and quit before your body ends up worse than when it began.."
If anyone think medical marijuana is bad, you have no dealt with a sick person or family member who might not survive his next few weeks without it. Medical marijuana has bad things in it yes, but the good outweigh it.
Exactly my thought, since when does the FDA ever approve something before knowing longer term effects.
have you ever actually read the bible
I dont think you should bring god into this, since everything doesnt need to be about religion. Consider this, although yes FDA is like that, but that still doesnt make up for all the other chemicals that there are in cannabis
As usual, NIDA misstates (or makes up) every factoid in this dreck. Shame on you. But then, you seem to have as hard a time recognizing shame as you do the science of medical cannabis. Of course, either way, you still cash your paychecks, don't you.
More govt BS propaganda.... Marijuana is a very effective medicine and HAS been proven.. Just use the web and a search engine. NEVER TRUST THE GOVERNMENT.
marijuana will wreck your life like a wrecking ball:)
The laws surrounding weed will. Not weed itself.
You have no evidence of that at all can you be more specific!!!!
In what way? Be specific
how bad
crack is bad and you will die dont be a crack head :)
marijuana will uptown funk u up
Hoestly i acctualy love u thanks for that reply that made my day
well very bad u can kill yourself
The most harmful effect known to stem from marijuana use, the one that has disrupted and destroyed the happiness and well being of so many could be cured by the stroke of the pen. The "il" in front of legal is the cause of more harm than any chemical contained within the plant. If it were legal and the Girl Scouts were selling it door to door I wouldn't by it or use it. But I can see the absurdity of prohibition. I smoke cigarettes which are known and proven to be more harmful, so what's wrong if someone wants to smoke another plant like marijuana?
Afterwards I searched on google and found this article useful for my study materials!! Very thanks
Actually, there are scientific studies. CBD has been shown to be enormously helpful for those suffering from epilepsy and neurological pain disorders. Many scientific studies are begun only to be stopped halfway through (by universities ending funding, etc) because of this insane "war on drugs" and because political ideologies are taking place over scientific discovery. Here is just one study that examines potential benefits of medical marijuana: Of course, as with ANY FDA approved (or otherwise) drug, everyone reacts differently and first time users should be cautious - this also applies to tylenol and every other over the counter or prescription drug!
I wish this article would provide an explanation why we need to arrest people.
I think people are going to abuse it.
Of course people will abuse it. Just like they abuse prescription pain medication. And Adderall. And Xanax. See, it's okay if those drugs are abused because there are big pharmacies that make those drugs and have lobbyists that persuade government officials not to regulate them more strictly (especially prescription opioids which are very addictive). Just a little food for thought!
you right
Some people shouldn't even give medical Marijuana. They can abuse it.
Soon all 50 states will allow medical hemp.
sooner or later weed will be leagal ever where because there are no real reasons that it shouldnt be. alchool kills more people in a year then anything else yet something thats never killed anyone is illegal, it jist doesnt make scense not to legalize marijuana.
Well, hang on a second here. Alcohol, which is sold legally does not necessarily kill more people each year than marijuana does. If the same amount of people each year used marijuana in the same manner as alcohol, then you could compare apples to apples. Since marijuana is not sold at every corner drug store and supermarket, you cannot compare the two. The amount of people in our country who are so stupid that it is amazing that their brain knows how to breathe, are now going to be on marijauna. Unbelievable.
weed is not bad for you!!!
Yeah marijuana is not that bad for most people but for others it can cause anxiety attack, respiratory issues, memory issues, some love handles, loss of motivation, psychotic episode. If any of these things happen to you its time to stop if you can once you get going. I mean it's a drug and will feel good or euphoric as they say and that will hinder your ability to stop when it starts messing with your priorities like most drugs do. "I was going to go to class but I was high...."
why wouldn't you do marijuana if you have pain and suffering? If theirs help you should take marijuana not suffer because its not legal
they need to make it safe before they uptown funk more people up