All You Need to Know About Cholinergic Urticaria

What is Cholinergic Urticaria?

Cholinergic Urticaria (CU) is a skin reaction that occurs when your body heats up, causing tiny red bumps or hives, often accompanied by burning or stinging sensations. It’s most often triggered by things that make you sweat, like exercise, hot showers, stress, or spicy food.

People aged between 10 and 30 are more prone to CU than others. Mostly, this skin condition improves as you age. In some rare cases, it may lead to a few health complications as well. However, there is no need to panic. The smart thing to do for such situations is to be prepared beforehand and buy health insurance well in advance. This ensures that you can easily get the medical attention you need without worrying about the cost.

Symptoms

Here are some of the early cholinergic urticaria symptoms you need to watch out for:

• Elevated red spots on your body, especially on your arms, face, upper back and chest

• Itchy and tingling sensations on the red spots

• Red spots formed around a broader area of redness in the skin (erythema)

• Tiny, red spots on the skin within 5 to 6 minutes of exposure to heat or sweat

• Warm feeling when touching the red spots

• Diarrhoea

• Increased saliva production

• Dizziness

• Headaches

• Palpitations

• Reduced blood pressure

• Wheezing or respiratory issues

• Abdominal cramps

In serious cases, symptoms may include:

• Development of hives all over

• Swelling of the skin near the face and lips, leading to blocked airways in some cases

• Difficulty breathing due to bronchospasm

• Low blood pressure (hypotension)

• CU with exercise-induced anaphylaxis, causing difficulties in breathing

In the initial stages, these hives may go off on their own after 30 minutes. However, for some people, the hives may fade off after an hour or two.

Causes and Risk Factors

The reason it happens is because when your body temperature increases, it stimulates the nervous system to release acetylcholine, which causes sweating. In people with cholinergic urticaria, this sweating process triggers an allergic-like response, leading to histamine release and hive formation. Other CU triggers include:

• Hot showers

• Fever

• Physical exertion from exercise

• Exposure to very hot climate conditions

• Wearing a tight bandage for extended hours

• Spicy foods

• Anxiety, anger, nervousness and other emotions that cause you to sweat profusely

According to experts, you are at a higher risk of cholinergic urticaria caused by heat and sweat if you have:

• Hay fever

• Asthma or respiratory issues

• Chronic skin conditions like eczema

• Profuse sweating, a condition known as hyperhidrosis

• History of hives or CU in the family

Diagnosis

When you seek medical help for an allergic reaction heat rash, doctors follow these diagnostic procedures to rule out other skin conditions and confirm if it is CU:

• Checking with you on how you feel in the affected areas

• Exercise tests, in which they induce sweating in your body through a series of intense physical routines

• Methacholine injections to check your body’s tolerance levels to acetylcholine and other cholinergic substances

• Passive warming tests, in which they increase your body temperature through hot showers or by exposing you to a sauna-like atmosphere

Treatment

Usually, the treatment methods followed includes:

• Antihistamines to control allergies

• Steroids or Histamine 2 Receptor Blockers

• Leukotriene Inhibitors

• Immunosuppressants

• Beta-blockers, such as Propranolol

• Anti-IgE monoclonal antibodies, such as Omalizumab

• Anabolic Steroids, such as Danazol

• Medicines to control asthma

• Medicines to control blood pressure

• Medicines to reduce sweat production

• Stress Management Treatments

• Phototherapy using ultraviolet rays

• Lifestyle changes (refraining from anything that increases body temperature or sweat production, avoiding spicy foods, quitting alcohol, etc).

Prevention Tips

While it may not be possible for you to completely avoid exposure to heat or sweating, you can try the following measures to reduce your risk of CU:

• Staying away from hot and spicy foods

• Engaging in outdoor exercise routines when it is not too hot (preferably early morning or late evening hours)

• A healthy lifestyle with effective stress management techniques

• Refraining from hot showers, hot baths or saunas

• Wearing comfortable, moisture-absorbing clothes

• Keeping your home temperature cool