Full Answer
What are the symptoms of urticaria?
Symptoms include a raised, red, itchy, welt-like rash with well-defined borders. Allergies and infections are common causes, but urticaria can also be triggered by cold, heat, pressure, vibration, stress, and even water. The location, timing, and look of the rash can provide clues as to what is causing it.
What is the difference between hives and urticaria?
"Urticaria" is the medical term for hives, which are red, itchy welts that can appear on the skin, sometimes accompanied by swelling. Hives can be caused by an allergic reaction, but some hives can appear without any known reason. 1 Hives usually disappear in about a day, but some hives can remain for weeks and require analysis by a doctor. 2
How long does urticaria last?
Chronic urticaria is often idiopathic and can recur over the course of months or years. In one 2013 study, 70% of people with chronic hives had symptoms that lasted for more than a year, while 14% had symptoms for five or more years. In half of the cases, no cause was found. 6
What is the difference between acute and chronic urticaria?
"Acute urticaria" is the term for hives that appear suddenly and last no longer than six weeks. 2 Chronic urticaria lasts for longer than six weeks and can appear suddenly or because of a known allergy. They can be very uncomfortable and interfere with sleep and daytime activities.
What are the symptoms of urticaria?
The effects of urticaria (hives) can be very noticeable, but the symptoms can be similar to those of other skin conditions such as eczema, rosacea, and pityriasis rosea. 1 While areas of hives on the skin (also referred to as wheals or weals) can vary in their distribution and appearance, they are characterized by itchy, raised welts on the skin's surface that are either red or skin-colored. 2
What percentage of people have urticaria?
Urticaria is known to affect up to 20 percent of the population and strikes people irrespective of age, race, or gender. 6 Hives most often appear in the evening or early morning just after waking. Itching is typically worse at night, often interfering with sleep.
How long do urticaria hives last?
Urticaria is classified as being either acute or chronic depending on the duration of the eruption. Acute hives last for less than six weeks, while chronic hives extend well beyond six weeks. 4
How long does it take for a urticaria to disappear?
The weals tend to appear five to 10 minutes after contact and generally disappear 10 to 15 minutes after they occur. 10 .
How long do hives last?
Chronic urticaria is defined as daily hives lasting for more than six weeks. 21.
What are the symptoms of vibratory hives?
While difficult to distinguish by looks alone, vibratory hives are sometimes accompanied by unusual symptoms such as flushing, headaches, blurry vision, or a metallic taste in the mouth. 14 . Water urticaria (aquagenic urticaria) is a rare form of hives caused by contact with water.
How long does it take for hives to go away?
Most will resolve within a few hours to several days. If it persists for more than a week or starts to worsen, see a healthcare provider as soon as possible.
Symptoms
Pathophysiology
- Urticaria is caused by an inflammatory reaction that prompts capillaries in the dermis (the layer of tissue just beneath the outer skin) to leak fluid. When this happens, the accumulation of fluid results in a defined area of raised skin that persists until the fluid is eventually reabsorbed into the surrounding cells.
Epidemiology
- Acute urticaria is more common in children and young adults. The majority are classified as idiopathic, meaning that we don't know the cause. Most cases are self-limited; individual lesions tend to resolve on their own within a few hours. An eruption rarely lasts more than several days, although it may recur over weeks. If a cause is found, it is usually related to an infection, insect b…
Treatment
- Chronic urticaria, by contrast, often requires medical treatment. In one 2014 study, 75 percent of people with chronic hives had symptoms that lasted for longer than a year, while 11 percent had symptoms for five or more years. In half of the cases, the offending agent was never found.
Signs and symptoms
- Urticaria is known to affect up to 20 percent of the population and strikes people irrespective of age, race, or gender. Hives most often appear in the evening or early morning just after waking. Itching is typically worse at night, often interfering with sleep.
Appearance
- The distribution and appearance of hives can vary significantly. Some may be widespread, while others may be diffuse or limited to a single, small weal. The appearance of a hive can sometimes give a clue as to the underlying cause.
Causes
- Less commonly, urticaria may precede a severe, all-body allergic reaction known as anaphylaxis. Anaphylaxis is often caused by a hyperallergic response that triggers the development of hives, angioedema (a related skin condition affecting deeper layers of tissue), and severe respiratory symptoms. Common allergy triggers are food, medications, vaccines, and ins…
Prognosis
- If left untreated, anaphylaxis can lead to shock, asphyxiation, coma, cardiac or respiratory failure, and death. If a case of hives is uncomplicated with no accompanying symptoms other than itching, you can usually treat it at home. Most will resolve within a few hours to several days. If it persists for more than a week or starts to worsen, see a doctor as soon as possible.
Diagnosis
- If your symptoms are recurrent and unexplained, ask your doctor for a referral to either a dermatologist, who can run tests to identify possible triggers, or an allergist, who can check whether an allergen (allergic trigger) is to blame. Your doctor may also want to check for undiagnosed infections (such as hepatitis B) or autoimmune diseases (such as Hashimoto's thy…