None of the allergens in cucumber have been recognised by the World Health Organisation, but it thought that the allergen responsible for causing allergic reactions are similar to proteins found in ragweed pollen.
Allergy to cucumber has been linked to Latex Food Syndrome, this is caused by the body confusing the proteins it encounters in food to that of latex proteins to which it is already sensitised.
You may have Pollen-Food Allergy Syndrome if you suffer from cucumber allergy with oral allergy symptoms to 3 or more of the foods mentioned in the cross reactivity section.
Those with a sensitivity to latex may have linked allergies to foods which contain high levels of chitinase, like avocado, chestnuts, corn (maize), kiwi, papaya, pomegranate and tomatoes.
If sensitised to Ragweed pollen you may also have problems with Banana, Melon, Courgette, and Squash