Urticaria

Urticaria (蕁麻疹, 風癩), also called hives is a common skin condition in which itchy, reddish, pinkish or flesh-colored bumps appear on the skin.

Causes of urticaria

There are many causes of urticaria, but usually, it is caused by the body's allergic reaction to specific external substances or environments, including:

Food, drugs
Environmental triggers or animal hair dander
Chemicals in food
Insect bite
Skin pressure
Sunlight
Sweating during exercise
Contact with cosmetics or hair dye
Parasites
Temperature, women’s period or psychological stress

Types of urticaria

Acute urticaria/angioedema

Symptoms usually last for 6 weeks. Common triggers include food, drugs, latex or infection. The most common rash-causing foods include shellfish, nuts, chocolate, fish, wheat and milk; triggering drugs include aspirin and nonsteroidal anti-inflammatory drugs

Chronic urticaria

Recurrent episodes occurring twice a week that usually lasts for at least 6 weeks. It is more difficult to identify the trigger than acute urticaria. The causes are similar to those mentioned above, and may also be caused by autoimmune diseases, chronic infections, hormonal imbalances or malignant tumors.

Cholinergic urticaria

Sweating caused by exercise, heat, stress, or eating spicy food

Dermatographia (Dermatographism)

Also called “skin writing”. Itching caused by scratching or rubbing the skin, especially when the environment is hot.

Solar urticaria (rare)

Rash after sun exposure, skin redness, swelling and itching

Cold shock urticaria

Rain, wind, and cold water can cause itching. Swimming in cold water can cause severe rash or even dizziness.

Aquagenic urticaria (rare)

Rash caused by contact with water, usually on the upper body

Contact urticaria

Appears within minutes of contact with chemicals, food, plants, animals, and animal products

Angioedema

Angioedema (swelling of the deeper layers of the skin) without hives can be caused by medications such as aspirin, ACE inhibitors, or food sensitivities

Hereditary angioedema

Swelling and pain in the face, mouth, throat and stomach are inherited in families and are caused by the lack of a certain protein in the serum.

Urticaria symptoms

There are 3 main categories of common symptoms, with severity depending on the symptoms and scope:

Rash: "rash" appears everywhere on the skin without leaving scars
Itching: There is usually an itching sensation in the rash, especially at night
Angioedema: Swelling in areas where the skin is thin, such as around the eyes and lips

How do I know if it is urticaria?

There are currently no specific tests for urticaria or angioedema. The doctor will study the patient's medical record to decide which test to use:

Regular blood tests to detect systemic diseases
Understand the patient’s medical history and the medications they are taking

Urticaria treatment

Identify what triggers it and try to avoid them
Take antihistamine medications as directed by your physician
Take oral corticosteroids from your doctor or prescription
Severe cases may require epinephrine injections or steroids
Taking immunosuppressants such as cyclosporine as directed by your physician

Prevention for urticaria

Avoid eating high-histamine foods such as alcohol, eggplant or dairy products
Relieve stress and avoid scratching
Use a food diary to find rash triggers
Avoid contact with hot water
Use mild, fragrance-free soap
Work and sleep in a cool room
Apply a cold compress or wet cloth to the rash area
Wearing loose clothing
Avoid foods that are fermented and contain a lot of coloring, preservatives or additives

OT&P Advice

There are many causes of urticaria, usually caused by the body's allergic reaction to specific external substances or the environment. Therefore, the main thing is to avoid known triggers first, and if you are unfortunate enough to develop it, avoid scratching, and take your doctor or prescribed oral medications such as antihistamines and corticosteroids. If you have any questions, please consult your family doctor.

References

Mayo Clinic. Chronic hives. 15 Sept 2023 Retrieved from https://www.mayoclinic.org/diseases-conditions/chronic-hives/symptoms-causes/syc-20352719
DermNet. Urticaria – an overview. 15 Sept 2023 Retrieved from https://dermnetnz.org/topics/urticaria-an-overview
Cleveland Clinic. Hives. 15 Sept 2023 Retrieved from https://my.clevelandclinic.org/health/diseases/8630-hives
American Academy of Dermatology Association. 10 WAYS TO GET RELIEF FROM CHRONIC HIVES. 15 Sept 2023 Retrieved from https://www.aad.org/public/diseases/a-z/hives-chronic-relief