Those who suffer from allergies know that the world is filled with all sorts of things that can threaten their health. Even the most innocuous items, such as peanuts, pollen, or cat hair can trigger anything from itchy eyes to full-on anaphylactic shock. Allergy sufferers learn how to cope by avoiding those things that can cause them trouble. What do you do, though, if you are allergic to something that seems impossible to avoid? Take a look at some of the weirdest allergies known to exist.

Water

Considering its prevalence and necessity for sustaining life, it is hard to imagine anything worse to be allergic to than water. Unfortunate suffers of aquagenic urticaria have to bear that burden. It is a rare condition that causes itchy and painful hives to break out whenever the individual comes into contact with water. There is no effective treatment, although anti-pruritic lotions or creams can help to soothe the itching.

All Food

The most common types of allergies are connected with food. Peanuts, wheat, and eggs are among the most common food items that will trigger dangerous reactions among allergy sufferers. Some people just can’t get a break, however. News reports in 2009 reported the story of Kaleb Bussenschutt, who was violently allergic to any kind of food and drink. Swallowing even a tiny particle of food would cause brutal ulcers to erupt in his stomach and cause him intense pain. The only drink he could handle was water and one specific brand of lemonade. Doctors still have not been able to identify the cause of his intense food allergies.

Sunlight

Next to water and all food, the most problematic allergy can be from sunlight. Called solar urticaria, sufferers break out in hives when exposed to the sun. Not to be confused with Porphyria (also known as Dracula’s Disease), those with this condition experience a release of histamines, nausea, and light-headedness when a significant part of the body encounters direct sunlight. Anti-histamines and sunscreen also help to keep reactions to a minimum, and although there is no permanent cure, in some rare cases the condition can go away on its own.

This allergy should not be confused with heat urticaria – another rare allergic reaction that occurs when the sufferer is exposed to temperatures greater than 109.4°F.

Exercise

Couch potatoes like to joke that they are allergic to exercise, but some people actually are. Exercise-induced anaphylaxis and urticaria are extremely rare and severe allergic reactions triggered by exercise. The symptoms include hives, gastrointestinal issues, and even anaphylaxis. Anaphylaxis is also known as anaphylactic shock and is potentially life-threatening, including symptoms such as light-headedness, a narrowing of the airways, and even collapse. It is no surprise, then, that in the case of anaphylaxis sufferers will be advised to only exercise with a partner, and will often be given an adrenaline shot to be taken in case of emergency.

Sweat

Related to exercise-induced allergy is an allergy to exercise’s byproduct: sweat. For people with cholinergic urticaria, any situation that triggers the sweat glands can be an itchy, painful scenario. In severe cases, it can even be life-threatening.

Electromagnetic Fields

Twenty-first-century life carries many benefits over the olden days, but there are occasional downsides, as well. A small group of people claims an allergy to electromagnetic fields. One individual, Debbie Bird, claims that her sensitivity to “electronic smog” is so intense she cannot operate any technology. To cope with modern life, she coated her walls with carbon paint and sleeps under a silver net to disrupt electromagnetic waves. Many doctors believe that the allergy is psychosomatic, but the jury is still out.

Money

Money is said to burn a hole in some people’s pockets. As it turns out, it can have a similar effect on the skin of some. For those who are allergic to nickel sulfate, just handling coins can trigger a rash. This allergy means that suffers must also avoid contact with shiny objects such as jewelry, metal parts of clothing, hairpins, lighters, and even some door handles. Gloves are recommended where money must be handled, and it is advised that sufferers of nickel allergies don’t carry loose change in their pockets.

Human Touch

Dermographism is an allergy to human touch — even one’s own. The name literally means “skin writing,” because suffers are able to write on their skin by simply touching it. It is a form of urticaria, and it tends to be a chronic condition. Symptoms can be minimized with antihistamines.

Apples Near Birch Trees

Identifying a particular allergy is a complex process. Sometimes the allergic condition is caused by the combination of more than one set of factors. Consider the case of Grace Morley, from Cork, Ireland. She likes apples and most of the time can eat them without any problem. She is also fond of birch trees and generally can spend all day around them with nary a concern. Put an apple near a birch tree, however, and you have a potentially deadly combination for her. The chemical combination of the two triggers a violent reaction that causes her head to massively swell and hives to break out all over her body. In minutes, her airway can close so completely that she will suffocate.

Vibration

Most allergies are triggered by physical substances. Occasionally, a person may be afflicted by an allergy to a non-physical property. Those who suffer from vibratory angioedema experience painful rashes by rapid movement. This rare allergy is triggered when a rapidly moving object, such as a motor, vibrating speaker, or anything that generates vibrations, is pressed against the skin. In just a few moments, the sufferer will experience very painful rashes and hives.

Humans

Lots of people have pet allergies. Did you know that animals also suffer from allergies, including allergies to humans? In 2014 an animal shelter in Indianapolis took in a Labrador named Adam who had some kind of unidentifiable skin irritation. Changes in diet, soaps and medications made no difference. Only after conducting an extensive allergy test did the veterinarians discover the cause of Adam’s suffering: he is allergic to humans.

Glitter

It is well accepted among civilized society that glitter is a blight upon humanity. When glitter gets on your skin, clothing, hair, or furniture, almost superhuman skill is needed to remove the shiny substance. For some people, glitter is more than an emotional irritant. Mica, a natural mineral that easily flakes apart to become glitter, is a common allergen that irritates the skin. Those who suffer from this condition also have to be on guard about many kinds of makeup, since mica is often found in such products.

Allergy Medication

Those who have allergies can generally find relief through over-the-counter allergy medications. Believe it or not, some people actually have an allergy to allergy medicine. Most who suffer from this allergy are actually reacting to the dyes and additives found in the medicines and not the anti-allergy chemicals themselves. If that is the case, they may find relief by searching for specially-made hypoallergenic allergy meds.

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