The ingredients that cause the side effects

Although the ingredients in propolis will depend on the location of the bee hives and the availability of plants, one allergen, called B1 is believed to always be present in propolis extract.

There are 3 main components in B1:-

• 3-methyl-2-butenyl caffeate
• 2-methyl-2-butenyl caffeate
• 3-methyl-3-butenyl caffeate

2-methyl-2-butenyl caffeate and 3-methyl-3-butenyl caffeate are believed to elicit strong reactions in patients known to be sensitive to propolis.

Other Allergen

Apart from the above, other potential allergens could be benzyl salicylate and benzyl cinnamate. These two allergen however, are considered to be mild sensitisizers and the number of reactions to these chemicals are less frequent that the three above.

Other ingredients in propolis – like essential oils, waxes, and flavonoids have been shown to have weak to no capability to induce allergies.

How high is the allergy risk?

It is generally acceptable to say that less than 10% of people are allergic to propolis.

However, the rate of sensitization to propolis or propolis derived products is actually much lower than that. It varies from 1.2% to 6.6% of the test patients.

Reference/Researchers	Total Patients Patch-Tested	Positive Reactions to Propolis
Hausen BM et al	3,177	38 (1.2%)
Guisti F et al	1,831	35 (1.9%)
Machackova J	605	25 (4.2%)
Reider N et al	433	28 (6.55%)
Francesca G et al	1255 children	5.9 %
Source : Medscape Today , PubMed

All of the studies above were done using patch testing method. The allergies reported were eczema and localized dermatitis on the faces, hands and limbs.

The last study involving 1255 children by Francesca G. et. al. was conducted for 8 years. The study concluded that less than 6 % of the test subject tested were allergic to propolis. Those who get contact dermatitis due to propolis were also found to be allergic to balsam of Peru ( which is not surprising since both products have common constituents).

A Word of Advice:
Please ask your doctor’s advice or ask for a patch test first before taking any propolis products. If you’ve used some propolis cream/products and appear to have the symptoms of allergy, discontinue the product.