When it's hot and I exercise, my skin becomes itchy all over. What kind of strange disease is this?

Have you ever had this experience? Sometimes after taking a hot bath or exercising, you will soon feel uncomfortable all over, with a particularly obvious itchy feeling, and even small mosquito bites on your skin. However, after a short time, these symptoms will disappear without anyone noticing after you calm down, and it will only take a few minutes.

If you have any of the above symptoms, then you are most likely suffering from "cholinergic urticaria".

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1. What is this strange disease called cholinergic urticaria?

In fact, cholinergic urticaria is not a strange disease, but a very common skin problem. Specifically, an average of 4 to 11 people out of every 100 have experienced this problem, and it is more likely to occur in people aged 10 to 30. Although many people have experienced this, they do not realize that it is a disease, so they do not pay special attention to it.

In the early stages of cholinergic urticaria, there are usually small bumps of 1 mm to 3 mm with some redness around them. In addition to itching, there may also be a tingling or burning sensation. Later, these redness can slowly expand and become a small red spot. More typically, these rashes usually appear on the body and neck first, and then slowly spread to the face and hands and feet; atypical cholinergic urticaria can start on any part of the skin. Cholinergic urticaria rarely has problems other than skin, such as fainting, low blood pressure, swelling of the skin, swelling of the eyes/lips, and shortness of breath.

In addition, you may be curious about how cholinergic urticaria occurs?

Simply put, it is related to a substance in our body called "histamine". When our body produces an immune response to certain specific stimuli, the body will release histamine, which will cause itching and rash, the typical manifestation of which is flaky redness or mosquito bite-like wheals.

2. How does cholinergic urticaria come about?

So, what kind of stimulation can cause these symptoms? In fact, the triggers of cholinergic urticaria vary, and each person's situation may be different.

To summarize, here are some common irritants:

Increased temperature: When the weather is hot or you take a hot bath, this external temperature change can passively increase the skin temperature or prevent the skin from dissipating heat normally, which can cause symptoms.

Exercise: Exercise may also trigger symptoms, especially strenuous exercise, which is more likely to trigger an attack in some people.

Sweating: This is because the sweating process can cause some complex physiological reactions, even if the core body temperature does not change can cause an attack. Sometimes even eating spicy food can cause this type of urticaria.

Emotional changes: Strong emotional fluctuations such as excitement and anger can also cause cholinergic urticaria through internal mechanisms.

Fever: Fever, which raises the body's temperature from the inside out, is also a common irritant.

In short, whether it is active or passive fever of the body, or exercise or emotional fluctuations, it can stimulate the characteristic manifestations of cholinergic urticaria. For individuals, you have to observe and summarize it yourself.

3. Tips for coping with cholinergic urticaria

So, what should you do when you experience these symptoms?

First of all, don’t panic. Although cholinergic urticaria is uncomfortable, there are some measures you can take to relieve the symptoms. Here are some suggestions:

Cold compress: When you feel itchy skin or mosquito bites appear, you can use a cold water towel to apply to the affected area to relieve itching and redness.

Avoid triggers: Try to avoid known triggers, such as high temperature, strenuous exercise, sweat stimulation, mood swings, etc. If the attacks are frequent, you can usually pay attention to record the environment and your own situation when the symptoms occur in order to find possible triggers.

Clothes with appropriate tightness: Choose loose and breathable clothes, avoid tight or rough materials to reduce friction and irritation to the skin, which may have a certain auxiliary effect.

If you are often troubled by cholinergic urticaria, or if the attacks are frequent and the itching is obvious, it is recommended that you see a professional dermatologist. The doctor can conduct a targeted assessment of your situation and provide more specific advice and treatment methods. If necessary, oral antihistamines such as cetirizine or loratadine will be added.

4. Can cholinergic urticaria be cured?

Unfortunately, there is no cure for cholinergic urticaria. Even though the above suggestions are very detailed, they can only help you relieve symptoms and improve your quality of life, not cure the disease.

Cholinergic urticaria is not like pencil writing on paper that can be erased with an eraser. Fortunately, it only occurs occasionally and at most causes short-term discomfort, without much impact on other aspects of health. As long as you can correctly understand it, prevent and treat it correctly, you can better reduce recurrence or control symptoms and maintain good skin health.

In addition, there is another good news, that is - cholinergic urticaria has a high probability of being cured without treatment, that is to say, without special medical intervention, it will heal on its own after a period of time, and it will not recur after recovery. For individuals, there is no way to predict when it will be cured without treatment. However, here are two research data based on the group perspective - one data is that about 70% of cholinergic urticaria will be cured within a few years, no more than 10 years; the other data is that the average duration of cholinergic urticaria is 7 and a half years, and if it is fast, it will even be cured in 3 years.

That’s all for today’s sharing. Are you familiar with this “strange disease” called cholinergic urticaria?

The article is produced by Science Popularization China-Starry Sky Project (Creation and Cultivation). Please indicate the source when reprinting.
Author: Tang Jiaoqing, attending physician of dermatology, doctor of medicine, popular science author reviewer: Cheng Fang, chief physician of dermatology, Xingtai People's Hospital, Hebei Province