Hay fever got you down? It could be worse.

Cold allergy

Being cold is unpleasant and uncomfortable, but a very small number of people are legitimately, and medically speaking, allergic to cold. It’s called cold urticaria. A reaction such as hives, bumps, or a swelling of the throat and tongue can result when exposed to any number of “cold” conditions, such frosty air, submersion in cold water, or even drinking ice-cold drinks. On a hot day, sweat on the skin mixed with a cool breeze can cause hives in a person with cold urticaria. While some symptoms (throat swelling) can be fatal, cold urticaria is generally easily treated with a common antihistamine.

Sun allergy

People with xeroderma pigmentosum probably hate getting compared to vampires, but that’s the frame of reference: it’s an allergy or extreme sensitivity to sunlight. (Technically, it’s an allergy to the sun’s ultraviolet rays.) People who have “the sunlight allergy” must be completely shielded from sunlight—they have to dress covered from head to toe, and avoid sunlight streaming in from windows. Even a little bit of exposure can cause severe sunburns and skin damage.

Water allergy

Even though the body is somewhere in the neighborhood of two-thirds water, people can still be allergic to water. Only a handful of cases of aquagenic urticaria have ever been recorded, although doctors don’t consider it a real allergy because it doesn’t trigger the same response as other allergies. However, those with the condition exposed to water suffer itchy hives and painful welts. Those with the “water allergy” must be very careful around water, and have to avoid submersion and can only take brief, and cold, showers. The main treatment for it? Topical application of capasaicin.