NIDA for Teens website is a project of the National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH). Created for middle and high school students and their teachers, this website provides accurate and timely information for use in and out of the classroom. (US)
Family First Comment: Politicians and the Drug Foundation should be forced to read this excellent summary from the USA’s National Institute on Drug Abuse (NIDA) and National Institutes of Health (NIH) before trumpeting law changes.
What’s Wrong With “Medical Marijuana”?
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:
- It’s hard to deliver precise, accurate doses of the right chemicals;
- It can harm the lungs if users smoke it; and
- 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.
So how can we discover and use marijuana’s medical benefits without the harms?
Making Medicine From Marijuana
This is the second post of a 3-part series on the science of medical marijuana. Check out Part 1: What’s Wrong With “Medical Marijuana”? and Part 3: Medicines or Poisons?—Why Cannabinoids Can Both Help and Hurt You.
What people usually mean by “medical marijuana” is use of an unprocessed (raw) plant to treat illness—or herbal medicine, in other words. Unprocessed means the leaves, stems, or seeds are just taken off the plant and used.
Before the 20th century, that’s mostly what medicine was.
But science has made a lot of progress in the last several decades, and generally it hasn’t looked back. It’s because we now have ways of picking out the specific chemicals that are useful from plants and putting just those parts in a pill, without all the unwanted chemicals that might cause side effects or even be toxic.
This is what a lot of scientists are busy doing right now with marijuana—trying to figure out which chemicals in the plant really are useful in treating health problems and then finding ways to deliver them safely and effectively to patients to treat their conditions.
Turning Marijuana into Medicine
At the last count, scientists have found over 500 separate chemicals in the marijuana plant. The main chemical that gives users the “high” is tetrahydrocannabinol, or THC, but there are over 100 other chemicals in marijuana that have a similar molecular structure to THC. This family of chemical compounds is called cannabinoids.
So far, there are two FDA-approved medications containing THC for treating nausea and appetite problems caused by cancer chemotherapy and AIDS. Other drugs with THC in them have been approved already in other countries for treating symptoms of multiple sclerosis (MS) and are now being carefully tested before being approved in the United States.
Another marijuana chemical is cannabidiol, or CBD. News reports have highlighted some families who are living in states where medical marijuana is legal so their children with bad forms of epilepsy can get special high-CBD marijuana extracts to help control seizures.
These extracts probably still contain other, possibly harmful ingredients. But a medicine only containing CBD is now being tested in the United States. If the science finds that CBD really is a good treatment for seizures, eventually patients may be able to take that or another safe, CBD-based medication. This could help people get the safe treatment they need.
Cannabinoids and Other Diseases
Lots of different cannabinoid chemicals are being studied to see whether they have beneficial effects on conditions ranging from addictions and other mental health problems to pain and other serious conditions. Most are still a long way from being studied in humans and going on to become medications.
Medicines or Poisons?—Why Cannabinoids Can Both Help and Hurt You
This is the final post of a 3-part series on the science of medical marijuana. Check out Part 1: What’s Wrong with “Medical Marijuana”? and Part 2: Making Medicine from Marijuana.
People who write about the health benefits of marijuana sometimes think it’s ironic that a plant containing compounds that could treat disease (like THC or CBD) is banned by the government for being unsafe. But in fact many effective, FDA-approved medicines are closely related to illegal, harmful drugs and are sometimes even made from the same sources.
That’s because there’s a fine (and sometimes fuzzy) line between chemicals that are good for you and those that can hurt or even kill you. In fact, the Greek word pharmakon, where we get pharmacy, originally meant both “medicine” and “poison.”
Speaking the Body’s Language
The opium poppy is a great example. It’s the source of a drug called morphine, part of a class of drugs called opioids. Morphine is used to make heroin—a very addictive and sometimes deadly drug. But it is also modified and used to make many effective, relatively safe pain relievers prescribed widely by doctors and dentists. In fact, these opioids are our most valuable drugs for pain relief.
Another example is cocaine, from the coca plant. It is part of a class of drugs called stimulants. Cocaine is an especially dangerous, addictive stimulant, but it is closely related to medications used to treat people with attention deficit hyperactivity disorder (ADHD) and other conditions. It is also used sometimes as an anesthetic.
The thing that makes a drug a drug is the ability to speak the body’s language—specifically, to interact with one of the many chemical signaling systems that cells use to talk to each other. Both heroin and cocaine are able to do that, fluently.
Same with marijuana: Its cannabinoid chemicals speak the body’s own endocannabinoid language.
Nerve cells use chemicals called neurotransmitters to send each other messages, and there are several different kinds of neurotransmitters. Similar chemicals in plants or in foods can interact with these neurotransmitter systems because their molecules are very similar to the ones produced naturally in the human body.
Morphine from the poppy plant is able to work in your nervous system because it closely resembles your body’s own natural pain-relieving opioid chemicals—the endorphins that cause a “runner’s high.” (The “endo” in endorphin or endocannabinoid means “from inside”—that is, inside your body.)
Cocaine and related stimulants work with your own neurotransmitter dopamine, which naturally keeps you focused on rewarding activities.
And the THC in marijuana interacts with the endocannabinoid signaling system used by the body’s own cannabinoid chemicals—such as anandamide—in brain circuits that control a wide range of things including pleasure, memory, thinking, concentration, movement, coordination, and even how you perceive time. That’s why THC is able to interfere with these abilities when people smoke marijuana either to get high or to treat a medical condition.
The endocannabinoid system also is involved in things like appetite and pain, which is why THC has been made into an effective medication for helping treat nausea and loss of appetite in AIDS and cancer-chemotherapy patients. And it is why it may, in the future, be prescribed for treating pain as well.
So, there’s nothing special about marijuana: It’s one of many plants that contain substances that can be both beneficial and harmful, depending on how they are used.