Story at-a-glance

• A case-study described a 34-year-old man who suffered anaphylaxis after stepping out of his shower and being met with cold air temperatures in his bathroom
• In addition to becoming covered in hives, the man struggled to breathe and was transported via ambulance to an emergency room
• While urticaria, or hives that appear suddenly, is thought to affect about 20% of people during their lifetimes, cold urticaria, or an allergy to cold temperatures, is relatively rare, with a reported prevalence of 0.05%
• Symptoms typically occur minutes after exposure of the skin to cold air, liquid or objects and are usually local, but anaphylaxis can also occur, especially if a large area of the body is exposed to cold temperatures, such as occurs during swimming in cold water
• In terms of prevention, avoiding exposure to cold is the most effective option, including ice-cold food and beverages, cold water and cold weather (using a scarf and clothing to protect skin when complete avoidance isn’t possible)

In Denver, Colorado, a 34-year-old man stepped out of a warm shower and was met with a rush of cold air from his bathroom — a familiar experience for many people during the fall and winter months. In this case, however, what is for most the sensation of a brief chill turned into a serious and potentially life-threatening allergic reaction known as anaphylaxis.1

In addition to becoming covered in hives, the man struggled to breathe and was transported via ambulance to the department of emergency medicine at the Denver Health Medical Center. There, he arrived with low blood pressure and shortness of breath caused by exposure to cold air after getting out of the shower.2

The condition, known as cold urticaria, is something emergency physicians should be aware of, doctors wrote in a case study published in The Journal of Emergency Medicine, as it can alter necessary patient care and may even be induced by cold IV infusions, leading to sudden declines in critically ill patients.3

Yes, Cold Air Allergies Exist

While urticaria, or hives that appear suddenly, is thought to affect about 20% of people during their lifetimes,4 cold urticaria, or an allergy to cold temperatures, is relatively rare, with a reported prevalence of 0.05%.5 Writing in UpToDate, Dr. Marcus Maurer, professor of dermatology and allergy at Charité Universitätsmedizin Berlin, Germany, explained:6

“Cold urticaria is characterized by pruritic wheals (hives) and/or angioedema due to cutaneous mast cell degranulation and release of proinflammatory mediators after cold exposure of the skin.

Triggers include skin contact with cold objects, cold liquids, and cold air. The underlying pathophysiology is largely unknown but is likely to involve immunoglobulin E (IgE)-mediated mast cell activation.”

With reported cases dating back to 1866, symptoms typically occur minutes after exposure of the skin to cold air, liquid or objects and are usually local, but anaphylaxis can also occur, especially if a large area of the body is exposed to cold temperatures, such as occurs during swimming in cold water.

It’s been suggested that most cases are self-limiting, resolving in four to five years. However, other research found only 25% of those affected have their symptoms resolve within 10 years.7 

Another study, which followed patients with cold urticarial from 1995 to 2015, revealed that while 22% reported their condition had resolved and 23% said it had improved, 55% said the disease remained stable or worsened over the study period.8 In other words, there are more questions than answers when it comes to cold urticaria, including its underlying cause.

In most cases, cold urticarial occurs without a family history of the condition, which suggests it’s not typically an inherited condition. Often, the event occurs without any obvious trigger, although infectious disease, insect bites, certain medications and blood cancers have been noted as possible factors.9

Young adults are most commonly affected, but at least one case study exists of a 9-year-old boy who developed cold urticarial after swimming in the ocean.10 One study also found that women may be affected twice as often as men.11

Signs and Symptoms of Cold Urticaria

Symptoms linked to cold urticaria vary from person to person. Some people may have mild reactions with few symptoms while others experience multiple symptoms and life-threatening anaphylaxis. Signs and symptoms include:12

Red, itchy rash after exposure to cold

Swelling in the area exposed to cold

Headache

Severe allergic reaction (anaphylaxis)

Trouble breathing

Shock

Passing out

Diagnosis is typically based on these characteristic signs and symptoms, but a cold stimulation test may also be done in which an ice cube or other cold object is placed against the skin for one to five minutes. If a red, swollen rash develops within a few minutes of exposure, cold urticaria is diagnosed.13

Blood tests may also be given to look for related diseases. In one study of 50 patients at an allergy practice in Vancouver, Canada, diagnosed with cold-induced urticarial, 32% had co-occurring physical urticarias while 52% had secondary allergy diagnoses.14

Because the condition can have a negative impact on quality of life, the primary goal of treatment is to alleviate symptoms. However, in terms of prevention, avoiding exposure to cold is the most effective option.15 In one assessment of 99 patients over a 20-year period, most relied on lifestyle modifications such as cold avoidance to control symptoms in lieu of medication.16

When this isn’t possible, antihistamines are sometimes recommended prior to cold exposures and those affected may also carry an epinephrine autoinjector (EpiPen) to use in the event of anaphylaxis.17 In the featured case study, for instance, physicians noted:18

“He required two doses of intramuscular epinephrine and was ultimately started on an epinephrine infusion. He was admitted to the intensive care unit for anaphylaxis monitoring and was found to have a positive ice cube test, reinforcing the suspected diagnosis.”

Largest Study to Date Sheds Light on Urticaria in Children

A study of children 18 years or younger diagnosed with acquired cold-induced urticaria (ACU) at Boston Children's Hospital shed some light on the condition in this age group.19 From 1996 to 2017, 415 patients, aged 4 months to 18.3 years, were diagnosed with ACU. The majority (78.3%) had a history of atopic disease while 25.8% had other urticaria.

Most of the cases (about two-thirds) led to only localized (Grade 1) symptoms, while 14% had symptoms that spread throughout the body (Grade 2) and 18.6% experienced anaphylaxis (Grade 3). In the most severe cases, which involved anaphylaxis, swimming was the noted trigger in 77.6% of cases while the rest were caused by ingestion of cold food or beverages or exposure to cold air or water.

The cold stimulation test (CST, such as the ice cube test described above), was used for diagnosis in 61.7% of patients, and was positive in 69.9%. The study authors explained:20

“In the largest study to date on ACU, grade 3 reactions occurred in about a fifth of patients. Positive CST result was associated with a higher risk for anaphylaxis from ACU. Epinephrine prescription and patient/family counseling about risk factors for grade 3 reactions are recommended.”

Living With Cold Urticaria

If you’ve been diagnosed with cold urticarial, you may need to avoid exposing large areas of your skin to cold water. Before you go swimming, for example, dip your hand in the water to see if a reaction occurs before jumping in, and do not swim alone in cold water.

You should also avoid ice-cold food and beverages and avoid exposing your skin to sudden changes in temperature as much as possible. Damp and windy conditions may make flare-ups more likely, while whole-body exposures to cold may lead to more severe reactions. If you’ve been prescribed an epinephrine autoinjector, keep it with you in case of serious reactions.21

During cold weather, you should also wear warm clothing and protect your skin from exposure to the elements as much as possible. A scarf wrapped around your nose and mouth, for instance, may be helpful.

As for alternative treatments, one study suggested that it may be possible to achieve desensitization by exposing small areas of the skin to cold, such as by washing your face with cold water every morning and evening. However, “For larger areas it can be a time-consuming procedure and requires close clinical supervision,” researchers wrote in the Journal of Investigative Dermatology Symposium Proceedings.22

Other Triggers for Urticaria

Urticaria, commonly known as hives, appear as raised red or skin-colored bumps on the skin. They may be itchy and will turn white in the center when pressed. Fortunately, cold-induced hives are not common, but they can be caused by many other physical triggers, including exposure to heat, pressure or sunlight. Exercise can also cause urticaria, as can:23

Certain foods, especially peanuts, eggs, nuts and shellfish

Medications, including antibiotics, aspirin and ibuprofen

Insect stings or bites

Latex

Blood transfusions

Bacterial infections, such as urinary tract infections and strep throat

Viral infections, including colds, mononucleosis and hepatitis

Pet dander

Pollen

Plants

Emotional stress

As is the case with cold urticaria, the best solution to hives is to avoid the trigger that causes them. In cases where the trigger isn’t obvious, and the hives are chronic, occurring for more than six weeks, speaking with an allergist may help.

Benefits and Risks of Cold Temperatures

Assuming you’re not allergic to the cold, exposure to cold temperatures can be beneficial to your health. Cold temperatures may help you burn body fat, and mitochondrial biogenesis is directly involved in this process.24 During exposure to cold, your body increases production of norepinephrine in the brain, which is involved in focus and attention.

Colder temperatures help you think more clearly25 and researchers have found that people perform tasks better when the room temperature is set at a cooler setting then a warmer one.26 Some of the simplest options to harness the power of the cold for your health include:

Applying an ice pack or cold gel pack

Applying an iced towel (simply wet a towel and freeze it) or massaging with ice cubes

Taking a cold shower or alternating between cold and hot in your shower

Taking an ice bath

Exercising in cold weather wearing few articles of clothing

Jumping into an unheated pool following sauna or exercise

Swimming in the ocean when water temperatures are low

Turning down the thermostat in your house in the winter to about 60 degrees F

There are some caveats, however. Your risk of heart attack rises with exposure to the cold as your blood pressure and risk of dehydration increase.27 This is especially true on days when pollution is high and temperatures are lower.28 Further, if you have signs of cold urticaria, you’ll want to avoid any unnecessary exposures to cold air, water, food or beverages.