Asking For A Friend: My sister is allergic to water

Aquagenic urticaria is a rare condition that causes itchy hives to develop when the skin comes into contact with water.

Karen Hawthorne 4 minute read June 10, 2022
Woman looking at glass of water in disgu

Those with aquagenic urticaria can safely consume water, but should avoid water to skin contact which would cause an allergic reaction. GETTY

Dear Asking For a Friend,

My sister was just told she is allergic to water. How do you become allergic? What are the risk factors and treatments, and can you drink water?

Signed, Can’t Live Without Water

 

Dear Can’t Live Without Water,

Yes, it’s true. There is a rare condition called aquagenic urticaria which causes people to have an allergic skin reaction to water.

If you thought coping with a stuffy nose, itchy eyes and sneezing during ragweed season when the plant’s pollen is released into the air was a major nuisance, things could be worse. Imagine getting nasty hives and bumps as often as several times a day when you come into contact with water. It can be devastating, interfering with work, social and daily life. And what about taking a shower or a bath? Walking in the rain is no picnic either.

“We just don’t know,” says Dr. Benjamin Barankin, dermatologist, medical director and founder of Toronto Dermatology Centre, when asked what causes a water allergy. “The water seems to cause a histamine release from mast cells in the skin that leads to hives, which is consistent with an allergy. Mast cells are immune cells in connective tissue throughout the body. They regulate immune responses, blood vessel formation and dilation, and overall balance.”

Barankin, who has served on the executive of the Canadian Dermatology Association and is a sought-after investigator in clinical research trials on skin conditions and treatments, says that no one has a full understanding of why aquagenic urticaria happens or the factors that could put you at risk.

What does a water allergy look like?

When people with the condition come into skin contact with water, they develop itchy hives — usually on the neck, upper torso and arms, although it can happen anywhere on the body. The hives are made up of red-coloured raised bumps on the skin called wheals that start to fade anywhere from 30 minutes to two hours after the skin is dry.

Aquagenic urticaria is particularly challenging because even contact with your sweat and tears can trigger a reaction.

“The rash can spread to affect areas that didn’t touch water,” says Barankin. “The wheals usually disappear within 30 to 120 minutes after stopping contact with water. People feel itching, burning and prickling.”

In rare instances, symptoms of wheezing and shortness of breath can occur.

Lack of scientific study

Boston University School of Medicine researchers reviewed the diagnostic and management challenges of the condition in the Journal of Asthma and Allergy, pointing to the lack of scientific study and the low numbers of people with the condition — estimated at about 50 cases in 2016. They findings showed that while there have been child-onset patients, aquagenic urticaria is more common in younger women and those with a family history. Symptoms can dissipate with aging.

Besides being uncomfortable, urticaria can have an impact on mental health as well. In fact, according to a Canadian review in Allergy, Asthma and Clinical Immunology of all types chronic urticaria — where hives can happen spontaneously or be linked to foods, infections, medications or insect stings — patients experience high levels of anxiety.

What kind of doctor treats urticaria?

Barankin says that urticaria is more commonly treated by an allergist, but it is seen in dermatology clinics periodically because of reactions to infections and medications. His clinic has a web page devoted to explaining urticaria.

Can someone allergic to water drink it?

And while we know that water is essential to keep hydrated and healthy, thankfully people with aquagenic urticaria can safely consume water. However, if any water comes into contact with the skin, there will likely be a reaction.

How is a water allergy treated?

The best treatment is to eliminate contact with water when possible, which can be tricky. Antihistamines can be prescribed to provide relief and are most effective if they’re taken on a regular schedule to prevent hives from forming.

“Non-sedating antihistamines are very safe and can be taken daily as a preventative, or one hour before exposure to water,” says Barankin.

An important takeaway is that you don’t have to figure out an allergy alone — see a dermatologist or allergist for treatment and ongoing care.

 

Karen Hawthorne is a Toronto-based writer.

Thank you for your support. If you liked this story, please send it to a friend. Every share counts.