Can You Get Sick From Weed?

can weed make you sick? young woman sick with headache from weed

You've heard it, said it, and most likely believe it: Cannabis is a healing herb. 

There’s an entire medicinal industry based around weed and for good reason. Marijuana is a naturally-occurring phenomenon – an empowering medicine packaged as a plant – that soothes inflammation, helps people with seizures, relieves a cancerous body, tackles migraines, defers nausea, and battles depression, one toke, topical, or brownie at a time. It is often considered miraculous, scientific, holistic, and medicinal all at once.

What if, though, a person doesn't feel better after lighting up? What does it mean when they instead get worse?

Can You Get Sick From Weed?

It's unlikely, but it can happen. Here are ways you might get sick from weed and how you might be able to remedy it. 

Too Much Weed/h2>
If you get sick after smoking or consuming weed, one rare – though possible – reason is over-consumption. While marijuana is noted for being non-toxic (again, the super food of smoked plants), it is conceivable to surpass your body's limit, especially for novice consumers and those who have grown dependent on their daily hit.

smoke from a jointA blood sugar drop is a surefire sign of ingesting weed, which, in serious cases, leads to nausea, sudden weakness, and even momentary unconsciousness. This rush of symptoms is referred to as a green or white-out, named for the onset paleness of the skin as the blood sugars deplete. Should this happen, consumers should have sugary snacks or drinks – not infused with cannabis – to help their systems regenerate.

Other signs of over-indulgence include shakiness and tremors, extreme dryness and cottonmouth (a common side effect that can reach intolerable levels with too much weed), and sometimes paranoia or psychosis. If you find yourself struggling with these symptoms, a good place to start is asking yourself if you should dial back the amount of cannabis you smoke, either at once or chronically.

As if Bad Weed Isn't Bad Enough

The most likely reason behind getting sick from weed is the weed itself: It's probably bad.

Creepy Crawlers

Pests are a problem that can lead to consumers feeling rough. There are several insects that cause more harm than good on cannabis leaves, including: aphids, thrips, whiteflies, gnats, green and black flies, caterpillars, inchworms, crickets, and spider mites. Sometimes bugs destroy the quality of the plant by chewing on the leaves and flower, while others make the cannabis their home. In doing so, they alter the cannabis, and the results are not kind.


With the legalization of cannabis, some growers want to protect their crops from the dangers of creepy crawlers and other chomping animals. In some cases, they turn to pesticides. When smoked, pesticides enter the body

Pesticides can make you sick when you smoke weed

Extreme pesticide exposure is linked to many health issues associated with getting ill. Here's the good news: It is extremely rare that pesticide-covered weed will get you sick—there have only been very few cases. Even better: There are regulations in place to ensure that consumers don't develop serious issues from contaminated marijuana, by cleaning up farming practices. All marijuana sold in dispensaries must go through regular, meticulous testing, and companies like Clean Green, Organic Cannabis Association, Certified Kind, and EnviroCann all offer certifications to ensure clean, pesticide-free weed. 

Moldy Weed

Cannabis is a plant, which means that it goes through the same problems as other leafy greens; one major concern is a moist environment leading to the growth of harmful bacteria and fungus, usually manifesting in mold.

Mold is toxic. And, sadly, marijuana makes for a great breeding ground for molds and mildew, especially when the plant has been exposed to moisture. Even more tragic, mold spores are able to withstand harsh environmental changes—like being heated up and burned. When a consumer then inhales this mold, hidden nicely into the density of the cannabis, the toxins are transferred directly into their body. In this scenario, weed can get you sick. 

Sickness is derived from compounds in mold, called endotoxins and mycotoxins. Mycotoxins exist on the exterior of mold spores. When they enter the body, these particles can trigger illness and irritation, especially when you smoke a large bowl of the bad stuff, and even more so if you do so often. Endotoxins are released by bacteria as they die—molecules that further agitate the body and can lead to lung irritation.

Types of Mold

Cladosporium, which commonly grows on wood or paper, can also be found in dampened cannabis. This plant fungus causes symptoms similar to hay fever and can cause pneumonia with lots of exposure over time. The fungus aspergillus, which produces a hefty number of mycotoxins, is known to cause lung infections and cause damage to immune systems. Gray mold, scientifically named Botrytis, is the most common weed mold: It usually gives consumers an allergic reaction.

moldy weed


Smoking moldy weed can increase the chances of infection and inflammation, and can aggravate existing autoimmune conditions. It can also cause a flurry of sickness, including headache, heart palpitations, dizziness, chest pain, memory fuzziness, fatigue, diarrhea, weakness, trouble breathing, coughing, vomiting, or an asthma-like attack. 

Cannabis Hyperemesis Syndrome>

There is one condition that has come to light in recent years, citing symptoms of severe nausea, cramps, and vomiting in weed consumers. First identified in 2004 in Australia, cannabinoid hyperemesis syndrome (CHS) is a potential reason behind weed-induced sickness.

Cases of CHS are few and far in between, and are rarely diagnosed or even studied by many doctors. Here's a high level summary of what doctors know:

  • Those who suffer from CHS tend to smoke weed a lot, qualifying under chronic and daily use.
  • The symptoms of CHS can come and go.
  • A hot shower can provide temporary relief from sickness, though it's unclear exactly why.

In a survey conducted in New York, however, 33 percent of recent hospitalized cannabis consumers mentioned having issues with nausea after smoking and found temporary relief after taking a hot shower. This figure can possibly translate to lots of people across the U.S. who have this condition and are unaware.

A University of Colorado professor of emergency medicine and medical toxicology and pharmacology named Dr. Kennon Heard has some ideas about CHS. Heard has spoken to NPR about the possible underlying causes of the condition.

woman visits doctor

Heard described CHS as a phenomenon taking place after at least six months of very frequent marijuana consumption, which then develops into severe abdominal pain and vomiting that comes and goes over several days. Heard also believes that smoking a lot of pot frequently can alter receptors in the body, cause some sort of dysregulation, and then trigger pain, though the specifics are still unclear.

CLICK HERE FOR MORE INFORMATION ON cannabinoid hyperemesis syndrome 

If you think you have CHS, get yourself checked out by a doctor. They can confirm whether or not you are getting sick from weed, or if it's a condition or something else going on in your body.

Be Proactive

If you get sick from your weed, you're one of the unlucky few. However, rather than wallow in despair, dig a little deeper.

Ask yourself: Is this an instance of overuse, either chronically or a one-time thing? Next, inspect your cannabis, looking for mold or mites. Source your marijuana and see if the growers were compliant with pesticide regulations. If the sickness continues, you might be one of the rare and unlucky cases of CHS; first, take a hot shower. Then, seek medical attention, especially if your body continues to reject the herb so heavily associated with healing.