Can You Be Allergic to Marijuana?

hands touching marijuana plant, which may cause some to wonder can you be allergic to marijuana

Reports of cannabis allergies are rising. Earlier this month, researchers even found the allergy in a child whose parents smoked pot at home. But the sharp uptick in reported allergies doesn't necessarily mean that more people are becoming allergic. Allergy sufferers may simply be more forthright with their doctors about their marijuana habits, as more states legalize pot.

If you're rolling your eyes, and thinking this "allergy" is just another piece of anti-pot propaganda, you can stop that right now. Cannabis allergies are absolutely real. Every time I touch my pot plants, I break out in hives. And I'm not alone.

The hives, itchiness, and sneezing don't prevent me from growing marijuana, because sneezing and feeling itchy seems pretty minor, compared to the profound ways pot has improved my life. But other people may not be so lucky. Other symptoms associated with cannabis allergies include rhinitis (inflammation in your nostrils), conjunctivitis (pink eye), and asthma.

A Wide Range of Symptoms

woman blowing her nose because she is congested, which is a symptom of cannabis allergiesAccording to the American Academy of Allergy Asthma and Immunology (AAAAI), your symptoms depend on how you were exposed. If you touch the plant, you can develop rashes, hives, or swelling. If you inhale cannabis allergens, you may develop a runny nose, sneezing, itching, and swollen, watery eyes.

There are even reports of anaphylaxis, which, if it leads to anaphylactic shock, can be fatal. However, this may only be linked to hempseed ingestion, not to marijuana itself. Hempseed is a common ingredient found in grocery stores across the country.

So to put things in perspective, if you're a highly allergic person, you're probably safer in a dispensary than you are in a grocery store.

Can You Be Allergic to Marijuana?

lots of marijuana plants in indoor cannabis grow

Cannabis allergies are still poorly understood, and more research is needed. New studies are underway, and scientists have already identified several ways cannabis may be an allergen. In the western U.S., for example, the AAAAI reports that cannabis pollen may be an airborne allergen, similar to ragweed. For people who are vulnerable to airborne allergens, it can cause respiratory symptoms.

But this doesn't really explain the allergies seen in indoor cannabis grows, where the plants are almost exclusively female. Female cannabis plants don't normally produce pollen. (Female cannabis plants are the ones that produce buds, the part of the plant we recognize as "pot.") The only time female plants produce pollen is when they're stressed, when they become hermaphroditic, in a last-ditch effort to pollinate themselves. (This is what growers refer to as "herming out.") This results in seeds in your weed, so it's highly undesirable – and, for most growers, uncommon. So, while pollen may be a factor in some cannabis allergies, it doesn't explain the allergies reported in cannabis grow facilities.

This has led some people to wonder whether cannabis allergies are really a result of cannabis itself, or a reaction to pesticides applied to the plant during its life cycle. For example, some individuals are allergic to neem oil, an organic pesticide commonly applied to marijuana plants. People may also be allergic to the more toxic pesticides used in some commercial grow facilities.

But some folks are definitely allergic to cannabis itself. (I grow my plants with nothing but sunshine and water, and I can't even remove a few leaves without hives spreading all over my arms.)

Allergic reactions are commonly reported among marijuana trimmers. Most professional trimmers wear long sleeves and gloves to prevent skin reactions.

What Causes Cannabis Allergies?

hands trimming marijuana, which can cause cannabis allergies in some people

Evidence suggests that some people may develop their cannabis allergies only after prolonged exposure.

Anecdotally, this appears to be true. Years ago, I trimmed happily in a variety of cannabis grows. I had no allergic reactions. I also worked in a dispensary, back when that involved a lot more contact with cannabis. (In the early days, medical marijuana was never pre-packaged; we weighed out each individual purchase. We also rolled joints by the thousands, and sold plants.) I've also toured licensed grow facilities all over Colorado. Hundreds of them, in fact. (I was Colorado's first state-approved wholesale weed broker, so I transported pounds in my Subaru nearly every day for several years.)

You could say I've had a bit of exposure. A couple years ago, my allergy appeared.

This is not uncommon for adult-onset allergies. Many adults are startled to discover they're suddenly allergic to a favorite food, like nuts or shellfish.

Researchers have found that most adult-onset allergies stem from what they call "cross-reactivity." In other words, my body may be recognizing marijuana as a relative of something else – something to which my body was allergic already.

And cannabis is apparently very cross-reactive. (This is ironic, because I smoke cannabis to avoid becoming either cross or overly reactive.)

"There is reported cross-reactivity between marijuana and certain foods," reports the AAAAI. "Cannabis cross-reacting foods that have been reported to cause allergy include tomato, peach and hazelnut."

Researchers at the Antwerp University Hospital in Belgium have named this the "cannabis?fruit/vegetable syndrome." In 2016, they found cannabis cross-reactivity with tobacco, natural latex, and plant?food?derived alcoholic beverages.

Children Can Experience the Allergy Too

marijuana joint leaving lots of smoke that can cause cannabis allergies

Earlier this month, researchers at the conference of the American College of Allergy, Asthma, and Immunology reported the first known case of cannabis allergy in a child. The six-year old boy had poorly controlled asthma. His adult family members, who often smoked marijuana at home, weren't exactly helping.

When they stopped smoking pot in the house, his asthma improved dramatically. Skin prick tests and blood tests confirmed that the boy was allergic to cannabis. Further tests indicated that cannabis allergies may have a genetic component: His grandmother, who sometimes broke out in hives after smoking pot, also tested positive for a cannabis allergy.

(Reading this, I recall that my mom, who's never smoked pot, became allergic to peaches, after spending her childhood eating lots of peaches. And peaches are cross-reactive with marijuana, according to the Belgian scientists. I must have inherited her gene for adult-onset cross-reactive plant allergies.)

These recent findings are important, because it's another huge reason to avoid smoking around kids.

"Children exposed to secondhand marijuana smoke can become allergic to cannabis," said the report's lead author, an Allergy and Immunology Fellow at National Jewish Health in Denver, Colorado. "[This] in turn may significantly worsen their asthma or allergy symptoms."

When any child has uncontrolled asthma, doctors should consider cannabis allergies as a possible cause, the doctor told Reuters.

More research is definitely needed. But it's clear you shouldn't smoke pot around kids, especially if they have other allergies or asthma. 

Possible Treatment Options for Cannabis Allergies

chocolate marijuana edible cookies

No treatments have been found. In the grand scheme of medical research, this probably isn't a huge priority.

"In the absence of a cure," the Belgian researchers concluded, "treatment comprises absolute avoidance."

If that seems unacceptable, you could experiment with some solutions. (Although, if you're severely allergic to cannabis, you should probably see a doctor. And if you experience anaphylactic shock for any reason, you should seek emergency room treatment immediately.)

If you're allergic to touching marijuana, you could try eating cannabis-infused food. Because while some people are definitely allergic to marijuana, nobody appears to be allergic to being stoned. So, edibles could be a great solution.

If your symptoms involve inflammation (like rhinitis), you could try treating them with cannabidiol (CBD). This non-psychoactive cannabinoid is known for its anti-inflammatory properties. You could try hemp-derived CBD to avoid further aggravating your marijuana allergy.

Maybe I'll give that a try, next time my cannabis allergy flares up. Luckily, I'm only extremely allergic to fresh plant matter, not dried and cured marijuana. (My allergy is basically a great excuse to ask my husband to trim our whole harvest every fall.) My allergies may get worse, as I've learned from researching this article. And I may suddenly become allergic to other things. In the meantime, I'm going to smoke pot, and eat a lot of peaches.