A new study published in the Annals of Allergy, Asthma & Immunology has revealed what may be a new allergy type: an allergy to cannabis.
The allergy is quite rare, researchers say, but as marijuana becomes legal in more areas, it may become more common. The allergy can be as mild as itchy eyes or as severe as producing anaphylactic shock.
The researchers from the American College of Allergy, Asthma and Immunology focused on the sativa strain of marijuana, one of two common "branches" in cultivated cannabis strains. Among those with an allergy to sativa, they found symptoms varied from asthma and eczema to anaphylaxis. The study examined cases of people who'd handled or smoked marijuana and then showed allergy symptoms.
Cannabis allergy rates may increase
“With state laws allowing medical and in some cases recreational use of marijuana, there is a growing potential for legitimate personal and commercial exposure,” the authors write. “The evolving legal status of [cannabis], its highly prevalent use throughout the world, and the varied forms in which it is used could translate into its growing role as a clinically relevant allergen that might be encountered.”
The study by ACAAI researchers coincides with similar research carried out in Belgium in 2014. Cannabis allergies are rare and similar to allergies to tobacco or tobacco smoke. The authors call for more research.
Ocampo T, Rans T. Cannabis sativa: the unconventional ‘weed’ allergen. Annals of Allergy, Asthma & Immunology. 2015.