A group of experts from the US, Canada and Europe are investigating allergic reactions to cannabis as the compound is being legalised in these countries. These medical experts, who recently formed the Cannabis Allergy Interest Group, conducted a survey of allergists in the US, Canada and Europe on their experiences with cannabis allergy and are planning to establish a registry and biobank to collect samples from patients to enable the development of better diagnostic tests. Cannabis proteins, which contribute to type 1 allergic reactions, act as high-molecular weight allergens. Hence, the experts stressed the need of a safe desensitisation or tolerance induction protocol on use of cannabis.