Although cannabis is generally deemed safe, it is possible to be allergic to it. You could also be allergic to the pesticides used on cannabis or common ingredients in cannabis product formulations. There’s also a rare genetic condition that causes some people to not feel “high,” regardless of how much cannabis they smoke or consume.
So, could you have a marijuana allergy? What are the signs and symptoms of cannabis allergies?
Known Cannabis Allergies
While our ancestors have used cannabis for millennia, reports of cannabis allergies are relatively more recent, with the first case being reported in 1971.
Although it was believed THC itself was the allergen, that doesn’t appear to be the case in emerging research. One study conducted skin prick tests on 23 individuals to assess their IgE antibody responses to various parts of the cannabis plant — the roots, leaves, buds, and flowers, to be specific.
Some of the patients had allergic responses to the roots and leaves, which are parts of the cannabis plant that wouldn’t even contain THC! So, what could be causing the allergy?
The study’s authors identified Glyceraldehyde-3-phosphate dehydrogenase as one of the potential allergens individuals may be reacting to. This protein is also a known allergen in wheat, rambutan, and several fungi.
Several other allergens were identified in their sample that could be potential mold or pollen allergens, including phosphoglycerate kinase and luminal binding protein.
In another review, several other cannabis allergens were identified, including:
- Profilin: An actin-binding protein found in both animals and plants. Foods commonly associated with profilin hypersensitivity include watermelon, muskmelon, citrus fruits, bananas, pineapples, tomatoes, and zucchinis.
- Nonspecific lipid transfer protein: An allergen found in fruits, vegetables, nuts, seeds, legumes, and cereals.
- Oxygen-evolving enhancer protein 2: A relatively new allergen that was first identified in Indian hemp.
- Pathogenesis related protein 10 homolog: A major allergen in tree pollen, food, and latex.
This review also suggests that certain cannabis allergens may correlate with having specific food allergies. For example, it was observed that individuals who are allergic to the nonspecific lipid transfer protein in cannabis may also have a peach allergy.
Pesticide Allergies and Cannabis
It’s also possible to be allergic to the pesticides used on cannabis and not necessarily the cannabis plant itself. Although some states have blocked the use of pesticides on cannabis, this isn’t the case across the entire U.S.
If you suspect this is the case, you can ask your allergist to conduct pesticide allergy testing to confirm your diagnosis. In the event of a pesticide allergy, you’ll need to shop for cannabis products from growers/processors who don’t use pesticides on their crops.
This can be difficult if you live in a state that hasn’t blocked the use of pesticides on cannabis plants. You’ll have to do a little digging to see which cannabis and hemp farmers in your area don’t use pesticides.
MCT Oil Allergies and Cannabis
Medium-chain triglycerides (MCT) oil is derived from coconuts and palm kernels. It is a common formulation in cannabis tinctures and other products because it’s high in fatty acids and cannabinoids are highly lipophilic. This means cannabinoids bind well to fats.
If you are allergic to MCT oil and not cannabis, make sure you read the ingredient labels on your products very closely.
Signs & Symptoms of Cannabis Allergies
According to the review mentioned above, a cannabis allergy can provoke type 1 and type 4 allergic reactions.
Type 1 (a.k.a. Type I) reactions are the most commonly recognized type of allergic responses. These reactions occur when IgE antibodies recognize a foreign antigen and attack it. Your body could respond in a number of ways, including hives, asthma, hay fever, or anaphylaxis.
Type 4 (a.k.a. Type IV) reactions are not as common in the realm of general allergies. While Type 1 reactions result from your antibodies being triggered, Type 4 reactions involve the other parts of your immune system, including helper T cells, lymphocytes, eosinophils, and monocytes activated by the antigen.
Additionally, Type 4 allergies are often delayed reactions. It takes 48 to 72 hours for the type 4 allergic reaction to occur.
Thus, symptoms of cannabis allergies could occur within minutes or within two to three days of using cannabis. Common symptoms of cannabis allergies include:
- Allergic Rhinoconjunctivitis: Nose and eye reactions, i.e., runny nose and sneezing; red, itchy, watery eyes.
- Hypersensitivity Pneumonitis: Inflammation of the lungs. Symptoms include a cough, shortness of breath, fever, chills, and headache.
- Allergic Keratoconjunctivitis: Inflammation of the eyes. Symptoms include red, itchy, watery eyes, swollen eyelids, and light sensitivity.
- Exacerbation of asthma symptoms: A cannabis allergy may worsen symptoms of an underlying asthma condition.
Cannabis allergies can be triggered by ingestion, inhalation, or skin contact with cannabis plants and products. You can also have an allergic reaction to cannabis pollen.
Can CBD Help with Allergies?
If you have non-cannabis-related allergies, there is some current and ongoing research about the role cannabinoids could play in allergy relief.
In an in vitro study on cell models of allergic contact dermatitis (allergic skin rashes), researchers tested the anti-inflammatory effects of CBD, CBDV, CBC, CBG, and THCV, as well as their raw/acidic forms to see if it could reduce the inflammation observed in allergic responses.
CBD, CBC, CBG, CBGV, and THCV were able to reduce various proteins and cytokines associated with skin allergies. However, their raw/acidic forms did not produce any observable effects. Of all the cannabinoids that were tested, CBD produced the strongest and most effective results.
Another study tested topical CBD products on individuals with inflammatory skin conditions, including atopic dermatitis, psoriasis, and scars.
“The topical administration of CBD ointment, without any THC, is a safe and effective non-invasive alternative for improving the quality of life in patients with some skin disorders, especially on inflammatory background,” the study concluded.
Thus, topical CBD products may help reduce the itchiness and redness of inflammatory skin conditions, including atopic dermatitis. However, research is still ongoing on the role CBD and other cannabinoids may play in other types of allergic reactions.
Not Getting High from Cannabis
While it isn’t necessarily an allergy, some individuals have a rare genetic condition that prevents them from feeling the “high” caused by THC — no matter how much they use or what products they try.
It is normal, perhaps even a “right of passage,” to not feel any noticeable effects the first time you try cannabis. This is typically due to not inhaling cannabis smoke or vape properly.
But when that has been ruled out by trying other products, such as gummies and tinctures, there could be another culprit at play.
While there is very little research on the condition that makes individuals “immune” to the effects of THC, it’s believed to occur based on which variant of an enzyme your liver produces. If you have this rare variant of the enzyme, your liver metabolizes THC into its active form and then its inactive form before it ever reaches your bloodstream.
Because the active form never reaches your bloodstream, you’re unable to “feel high” from marijuana.
Key Takeaways: Cannabis Allergies Aren’t Caused by THC
Despite humans’ lengthy history with cannabis, the first cannabis allergies weren’t reported until 1971. Initially, it was believed THC may be the cause of cannabis allergies, but according to emerging research, that doesn’t appear to be the case.
Instead, it seems cannabis plants possess several potential allergens found in other fruits, vegetables, and plants. Certain food allergies also seem to correlate with cannabis allergies, too.
In the case of non-cannabis-related allergies, there’s also ongoing research on the efficacy of cannabinoids for alleviating certain types of allergic reactions, including atopic dermatitis.
Lastly, while it isn’t an allergy, some individuals appear to be “immune” to the effects of THC. This means no matter how much cannabis they use, they simply can’t get “high.”
Although this topic is still under investigation, some individuals possess a rare liver enzyme that metabolizes THC a bit too efficiently. In essence, their liver turns THC into its inactive form before it ever reaches the bloodstream.
If you are allergic to cannabis, it is recommended that you avoid flower and other full-plant extracts. Reportedly, some individuals who are allergic to cannabis plants can tolerate isolates, extracts, and concentrates that contain no plant matter. But if you have a severe cannabis allergy, it’s probably best to avoid any cannabis products just to be safe.
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