Hives: Testing Methods and Treatment | Rohto Pharmaceutical: Product Information Site

<Things you should know> Correct knowledge about "urticaria" (3) Methods of testing and treatment for urticaria

Hives testing and treatment
Methods to suppress hives
Be careful of worsening (severe) hives.

It is said that about one in four or five people will develop hives. This means that a very large number of people will experience hives at least once in their lifetime. Finally, we will look at the tests and treatments for hives, as well as ways to suppress them.

Hives testing and treatment

Treatment for hives begins with identifying the type of hives. Once the cause of the hives is identified, the best treatment is to eliminate that cause.

Tests to investigate the cause include blood tests, skin tests, provocation tests, stress tests, and skin biopsies (taking a small sample of skin for examination). These methods help identify aggravating and triggering factors.

One blood test method is the IgE antibody test. IgE is a factor that reacts to allergens, causing mast cells and other cells to release histamine. A blood sample is taken to check if the reaction to the causative substance is elevated. If shellfish is the allergen, the result will show "high IgE levels to shellfish."

If you can't get to the hospital immediately when your baby or child develops hives, you can try cooling the affected area to soothe the itching, unless it's cold urticaria. Also, keep them at rest to avoid increasing blood flow.

Next, we will look at countermeasures for hives caused by food allergies, which are common in children. We will explain them below, categorized by the foods that are likely to cause them.

Egg allergy

If eggs are the allergen, a positive IgE reaction to egg whites or ovomucoid (one of the substances that cause egg allergies) is checked. Depending on the reaction, the appropriate course of action will differ: should you avoid all egg-containing foods such as cakes and cookies, or should you avoid eggs themselves, such as in omelets and rice dishes? Even if you react to raw eggs, you may be able to eat them if they are cooked.
Wheat allergy

If wheat is the cause, the solution is to reduce your intake of wheat products, although small amounts may not be a problem in some cases. It's also important to be careful with products containing gluten, not just wheat.
Milk allergy

If an infant has a milk allergy, formula milk (artificial milk) is fine because it is primarily made from cow's milk. Similar to eggs, the decision of whether to avoid all dairy products or simply avoid cow's milk depends on the test results.
Soy allergy

While soybeans are generally considered to retain their allergenic properties even when heated, processed soy products can sometimes weaken these allergens. Typically, soybeans, peanuts, and okara (soy pulp) evoke strong reactions, while processed products like tofu, soy sauce, and natto tend to evoke weaker reactions. However, it's known that soy milk can trigger allergic symptoms in individuals with birch pollen allergy.

Methods to suppress hives

In cases of allergic urticaria, symptoms usually subside naturally simply by avoiding allergens, triggers, and aggravating factors. If the cause cannot be identified and the symptoms persist, treatment will involve medication.

First, there are antihistamines to suppress the effects of histamine, which is the cause of itching. However, as explained in (1) the cause and mechanism of hives, histamine is a neurotransmitter in the brain that controls wakefulness, memory, and appetite suppression, so taking it can cause side effects such as drowsiness, lethargy, and increased appetite. For this reason, people who drive or do dangerous work must be careful when taking it. Antihistamines are classified into first-generation and second-generation drugs. First-generation drugs have a shorter duration of effect and act more easily on the brain, while second-generation drugs have a longer duration of effect and act less easily on the brain compared to first-generation drugs. In addition, if antihistamines are ineffective, H2 blockers, which suppress stomach acid, can be used to enhance the effect of antihistamines.

Other medications used to treat urticaria include topical creams containing steroids and antihistamines, and anti-leukotriene drugs, which are prescribed according to the symptoms. In cases of allergic urticaria where the cause has been identified, treatment may involve immunotherapy using specific allergens. There is also a treatment method that involves subcutaneously injecting antibodies against the entire protein called IgE, which is the cause of urticaria, to suppress the allergic reaction of IgE.

Be careful of worsening (severe) hives.

If the cause of hives has been identified and is not removed, the hives will persist. If you have a food allergy and eat the offending food, and continue to eat it despite developing hives, you may experience anaphylaxis, where the hives spread throughout your body or trigger asthma. In some cases, exercise or bathing, which improves blood circulation throughout the body, can worsen hives, causing them to spread and the entire body to become itchy. Alcohol can also worsen the condition for the same reasons, so it's best to refrain from drinking alcohol.

Source: "The True Common Sense of Hives" by Kunihiro Kiyomasu (Medical Economics Co., Ltd.)

Supervised by: Dr. Kunihiro Kiyomasu, Head of Pediatrics, Yamato-Takada Municipal Hospital
He graduated from Kyoto University Faculty of Medicine in 1992 and from Kyoto University Graduate School in 1999. He holds a PhD in Medicine and is a certified specialist and instructor of the Japan Pediatric Society and the Japanese Society of Allergology. His publications include "Common Sense and Uncommon Sense in Atopic Dermatitis Treatment" (Iyakukeizai-sha) and "The 'True' Common Sense about Urticaria" (Iyakukeizai-sha).

We take care to post accurate information,
Please point out any incorrect information.

Please submit any comments regarding medical information here.

Return to the list of guides categorized by health symptoms.