How does cannabis get you high?
How do marijuana’s psychoactive properties work?
Have you ever looked at your hands? I mean really looked at your hands?
You might think you have, but as the above classic Doonesbury cartoon implies, people who are high on cannabis may perceive mundane objects to be far more fascinating than usual.
How is it that a plant that first emerged on what’s now the Tibetan Plateau can change humans’ perception of reality? The secret lies in a class of compounds called cannabinoids. While cannabis plants are known to produce at least 140 types of cannabinoids, there’s one that’s largely responsible for many of the effects of feeling high. It’s called tetrahydrocannabinol, or THC.
When a person smokes or inhales cannabis, THC “goes into your lungs and gets absorbed … into the blood,” according to Daniele Piomelli, a professor of anatomy & neurobiology, biological chemistry, and pharmacology at the University of California, Irvine School of Medicine. Edibles take slightly longer trip through the liver, where enzymes transform THC into a different compound that takes a bit longer to have an effect on people’s perception of reality.
THC that’s inhaled “reaches pretty high levels fairly quickly,” Piomelli told Live Science. Within 20 minutes, the circulatory system is carrying molecules of THC to every tissue in the body, including the brain, where it can alter neural chemistry.
“From the lungs, it’s a pretty straight shot to the brain,” according to Kelly Drew, a professor of chemistry and biochemistry at the University of Alaska Fairbanks.
The THC molecules that pass the blood-brain barrier will find that they fit snugly into receptors that ordinarily receive compounds called endocannabinoids, which the body produces itself. These receptors are part of the endocannabinoid system, which is involved in several functions, including stress, food intake, metabolism and pain, according to Piomelli, who also directs the Center for the Study of Cannabis at UC Irvine.
“The endocannabinoid system is the most pervasive, diffused and important modulatory system in the brain because it controls the release of pretty much every neurotransmitter,” Piomelli said. Neurotransmitters are molecules that brain cells, or neurons, use to communicate with each other. One neuron sends a message to the next by releasing neurotransmitters, such as dopamine or serotonin, into an infinitesimal gap that separates one neuron from the next. The gap is called the synapse.
The neuron on the receiving end of the synapse is called the postsynaptic neuron, and it “decides whether to fire based on the input it receives,” Drew told Live Science. These neural signals cascade through intricate circuits of neural connections that function on a tremendous scale; there are about 85 billion neurons in the brain and as many as 100 trillion connections among them.
The presynaptic neuron sends neurotransmitters across the synapse to the postsynaptic neuron, Piomelli said. But the presynaptic neuron can also receive information. When a postsynaptic neuron has fired, it can send a message across the synapse that says, “the neuron I come from has been activated,” stop sending neurotransmitters, Piomelli said. It sends this “stop” message in the form of endocannabinoids that bind to a receptor called cannabinoid 1 (CB1).
“Like a sledgehammer”
When THC enters the brain, the molecules diffuse into the synapses where they “activate CB1 receptors,” Drew said. THC doesn’t cause the most extreme possible response like some synthetic cannabinoids such as K2 or spice, but it does “turn up the volume” and increase the likelihood that the presynaptic neuron it affects will temporarily stop sending neurotransmitters, she said.
“The high is a very simple phenomenon, Piomelli said. “THC comes in like a sledgehammer,” flooding the endocannabinoid system with signals the postsynaptic neurons didn’t send. When presynaptic neurons across the brain get the memo to stop sending neurotransmitters, this alters the normal flow of information among neurons and results in a high.
Scientists have yet to decipher exactly what happens during this euphoria, however.
That’s because, in part, U.S. legal restrictions make it difficult to study cannabis. But from what researchers have gathered so far, THC appears to temporarily “unplug” the default mode network. This is the brain network that allows us to daydream and think about the past and future. When our brains are focused on a specific task, we quiet this network to let our executive function take control.
There’s evidence that THC has a significant effect on the network, but researchers aren’t quite sure how it happens. There are cannabinoid receptors all over the brain, including in “areas that constitute the key nodes of the [default mode network],” Piomelli said. It could be “that THC deactivates the [default mode network] by combining with those receptors,” but it’s also possible that THC quiets the network through an “indirect effect that involves cannabinoid receptors in other brain regions.”
Scientists are still working to find the mechanisms that result in a person feeling high, but there’s some reason to think this effect on the default mode network is a significant piece of the puzzle.
Unplugging the default mode network “takes us into a mental place where the function of the things we experience is less important than the things themselves: our hands are no longer just something we use for touching or grabbing, but something with inner existence and intrinsic value,” Piomelli said. Psychedelics, such as LSD or dried psilocybin-containing mushrooms, do the same thing.
However, people can experience highs differently. “The feeling of becoming fascinated by and ‘connected’ with ordinary things, things we see and use every day, is not universal but does happen, especially when high doses of THC-containing cannabis are used,” Piomelli said.
THC doesn’t just affect the default mode network. It may also, in the short-term, flood the brain with dopamine, the brain’s reward signal, according to a 2017 study in the journal Nature. (Long-term, it may blunt dopamine’s effects, the study found.) That, in part, may explain some of the euphoria associated with a high, and places cannabis in the company of other drugs that people use to feel pleasure.
“Every drug that has rewarding properties affects that system,” Drew said.
The effects of a high from cannabis that’s smoked or inhaled typically last for a few hours, though it can take edibles almost that long to start affecting users. And while cannabis isn’t the dangerous substance it was made out to be in the 20th century, using it comes with some risk. For one, while cannabis is legal for recreational and medical use in some states, it’s still illegal in many parts of the country.
It’s also important to bear in mind that cannabis is a potent pharmacological substance. Cannabis can cross the placenta, so pregnant people should avoid it. And “heavy use in the teenage years can be problematic,” Piomelli said. For instance, cannabis — and especially synthetic cannabinoids like spice — can exacerbate psychosis. “People who are at risk for that should not smoke it,” Drew said.
Finally, cannabis does affect the ability to drive, particularly in occasional users. Drew cautioned that people should not drive for three hours after smoking.
Eventually, the THC will leave the brain; the profusion of blood that brought THC into the brain will carry it to the liver, where it will be destroyed and expelled in urine.
And you’re not gonna believe this, but your hands — they were the same the whole time.
Originally published on Live Science.
IMHO, drugs which do not easily cause overdose deaths (like THC, LSD etc) should/must be legally treated same as alcohol (which is really just another kind of drug (which do not easily cause overdose deaths))!
IMHO, just like prohibition of alcohol had caused so much crime in the past (& that is why it had been forced to be repealed later), prohibition of other similar drugs causing so much easily preventable crime today!
We need to take lesson from our past.
It gives people relief without vice.
This is precisely why it has been vilified for so long. You cannot have such things. Fun, pleasure and relief without vice?
That is blasphemy of the highest order for the “divinely” inspired. In their distorted concept of “dealing with life”, you have to tough it out. Anything which circumvents such rigors in life is sinful.
It reminds one of the famous counter-culture response: “Reality is for people who cannot deal with drugs.”
Stay up to date on the coronavirus outbreak by signing up to our newsletter today.
Thank you for signing up to Live Science. You will receive a verification email shortly.
There was a problem. Please refresh the page and try again.
Here’s how cannabis jumbles up typical brain processing.
Is There a Safer Way to Smoke Cannabis? How the Methods Stack Up
If you’re looking for the healthiest way to smoke cannabis, keep in mind that there’s no totally safe way to do so — even with the purest, most pesticide-free bud. Cannabis smoke contains most of the same toxins and carcinogens that make tobacco smoke harmful to your health.
There are, however, methods that may be slightly less harmful than others. Here’s a look at how different methods compare, plus some smoke-free alternatives to consider.
The dangers of smoke inhalation are well known, so it’s not surprising that a lot of folks assume vaping is the healthier alternative to smoking. Unfortunately, it’s not that simple.
There’s mounting evidence that vaping can have serious health effects. Much of the concern comes from inhaling vitamin E acetate, a chemical additive found in many vaping products containing tetrahydrocannabinol, or THC.
However, this risk seems to apply only to vaping concentrates, not flower. A 2006 study suggests that vaping actual cannabis, not concentrate, is less harmful to your respiratory system than smoking. Still, research on vaping cannabis is pretty limited.
Lung health aside, there’s also a matter of potency. People who vape cannabis report experiencing stronger effects — regardless of the amount of THC in the product — than they do when smoking. This means a higher chance of overdoing it, or greening out, when vaping.
Maybe a teeny, tiny bit, but nowhere near enough to make a difference.
Bongs offer a smoother toke because you don’t get the dry heat from smoking cannabis rolled in paper. Though it feels less harsh when you inhale, your lungs don’t know the difference.
Well, both still involve inhaling smoke, so there’s that. But if you had to choose the lesser of two evils, joints are probably the better option. This is because blunts are made with hollowed-out cigars, and cigars and their wrappers are highly toxic.
Even after removing all the tobacco from a cigar, cancer-causing toxins, such as nitrosamines, can remain. Plus, cigar wrappers are more porous than rolling papers, so the burning is less complete. This results in smoke with high concentrations of toxins.
Then there’s the matter of size. Blunts are a lot bigger than joints, and they hold way more pot. Smoking an entire blunt is like smoking roughly six joints.
Dabbing is supposed to give you a “cleaner” high, but what does that actually mean? Not much.
Budder — another name for dabs or marijuana concentrate — delivers a lot more THC than other weed products, often as much as 80 percent more.
Dabbing is still pretty new, so experts still don’t know the full impact.
There’s evidence that exposure to high THC may lead to long-term mental health effects, like psychosis. The risk of misuse and addiction is also higher when using high-THC products, especially for young people.
Plus, unless you have high-tech lab equipment and are trained in extraction, your dabs may be far from pure. Research shows that dabs can contain contaminants and residual solvents that can to neurotoxicity and cardiotoxicity.
Dabbing also has respiratory effects, even though you’re not technically “smoking.” There have been cases of people developing lung damage from dabbing.
The bad news? There’s no safe way to smoke cannabis. The good news? There are plenty of other ways to consume it.
Here are your main options:
- Edibles. Unlike smoking and vaping, ingesting cannabis won’t harm your lung health. The downside for some is that edibles take longer to kick in because they need to clear your digestive system before getting into your bloodstream. The upside is that the effects also hang around longer. You also have an endless variety to choose from, with everything from gummies to baked goods to cannabutter.
- Sublinguals. These are usually lumped together with edibles, but they’re not quite the same. Unlike edibles, you don’t actually swallow sublingual forms of cannabis, which include things like tinctures, films, and dissolvable tablets. Sublingual cannabis is placed under the tongue for absorption, and is absorbed through your mouth’s mucus membranes, so the effects are felt faster.
- Tinctures. Tinctures are made of alcohol-based cannabis extracts that come in bottles with droppers. You can add tinctures to drinks, but you can also get the effects faster by placing a few drops — depending on your desired dose — under your tongue.
- Topicals. Cannabis topicals are for people looking for the therapeutic benefits of cannabis without the cerebral effects. Creams, balms, and patches can be applied to the skin to relieve inflammation and pain. There’s also cannabis lubricant made for, well, sexy time.
- Suppositories. The idea of shoving cannabis up your butt (or vagina, depending on the product) may make you clench, but it’s definitely a thing. Most of the suppositories on the market are CBD-infused and used for therapeutic reasons, like pain or nausea relief, but some brands have upped their THC content for added effects.
If you’d still rather smoke your weed despite the risks, consider these harm-reduction tips to help make it a little safer:
- Don’t hold the inhale. Inhaling deeply and holding it in exposes your lungs to more tar per breath. Don’t be greedy; exhaling faster is better for you.
- Use rolling papers approved by the Food and Drug Administration (FDA). Rolling papers may seem like NBD, but some contain chemicals and flavorings that can be toxic.
- Stick to glass bongs and pipes. Plastic bongs can contain chemicals like BPA and phthalates, which have been linked to serious health effects, including cancer.
- Keep your stuff clean. Keep your bongs and pipes clean, and don’t roll your weed on dirty surfaces.
- Don’t share mouthpieces or pass joints. Sharing your stash is fine, but not your pipes, bongs, or joints. When you share these, you’re basically swapping spit with that person and putting yourself at risk for infections.
No matter how you dice it, there’s really no safe way to smoke cannabis, whether you prefer to roll one up or are partial to bongs. As cannabis becomes more popular, so do products that allow you to indulge without the smoke.
That said, if you’re partial to puffing and passing, a vaporizer that allows you to use flower, not concentrates, may be a less harmful option.
Adrienne Santos-Longhurst is a freelance writer and author who has written extensively on all things health and lifestyle for more than a decade. When she’s not holed-up in her writing shed researching an article or off interviewing health professionals, she can be found frolicking around her beach town with husband and dogs in tow or splashing about the lake trying to master the stand-up paddleboard.
You can smoke cannabis in a variety of ways, but is one safer or healthier than others?