Types of Hives
According to the American College of Allergy, Asthma and Immunology, hives affect 20% of the population at least once during their lifetime. It’s one of the most common skin disorders, and there are dozens of triggers for it. Contrary to what some believe, there are many types of hives, each with its own manifestations.
Although, in general, the condition doesn’t represent any type of risk for people, it’s recommended that patients with recurrent episodes should seek medical assistance to maintain control of the flare-ups. Today, we’ll bring you a guide to the most common manifestations of the condition.
How many types of hives are there?
Hives aren’t just one single condition with specific characteristics, evolution, or triggers. In fact, it groups together a series of skin manifestations that produce rashes that are accompanied by inflammation and itching. It isn’t always easy to make the distinction, as the dividing lines between episodes are very thin.
The Association of People Affected by Chronic Urticaria, based in Spain highlights the following types.
1. Spontaneous urticarias
The development of skin symptoms without an apparent trigger is known as spontaneous urticarias. Signs develop within minutes and can affect any part of the body. Patients can’t predict when episodes are going to occur, nor can they do anything to prevent them. According to its duration, two subtypes are distinguished.
These episodes can last a couple of hours, a few days, or even up to 6 weeks. Columbia University Irving Medical Center points out that the possible causes of these conditions are food allergies, blood transfusions, insect bites, and infections. The latter are a major driver, and you can develop a rash after getting a common cold.
Other possible triggers are exposure to certain medications (such as penicillin and sulfa drugs) and stress. As the Global Allergy & Airways Patient Platform well points out, episodes are often accompanied by anxiety, as patients can’t find a reasonable explanation and reactions can be intermittent while they disappear.
It also occurs spontaneously, but, in these cases, the symptoms can last for more than 6 weeks. There’s no average limit for these manifestations; they can last a couple of months or even years without the exact cause of the outbreak being found. Some researchers point out that up to 50% of reactions of this type have an autoimmune background.
Other studies suggest that parasite infection can also trigger it. Despite these theories, there’s no consensus on triggers.
An article published in 2009 in the European Journal of Allergy and Clinical Immunology indicates that in one in three patients the intensity of symptoms is reduced if a pseudo-allergen-free diet is maintained.
Since this variant can last for years, and there’s no standard treatment, eliminating certain food groups can be an affordable, easy, and practical palliative. This gives good results to a significant percentage of patients with chronic urticaria.
2. Physical urticarias
In the previous types of urticarias, the exact trigger of the cutaneous manifestation is unknown. With physical hives, the opposite is true, and so patients can make changes to their lives to reduce flare-ups. There are many subtypes, among which we can highlight the following:
- Cold urticaria: As its name suggests, it’s triggered in the presence of low temperatures. Some studies suggest that its prevalence is around 3%. It can be accompanied by a cold or classic allergy symptoms.
- Heat urticaria: This manifests when the temperature increases, regardless of whether the patient is directly exposed to the sun. Researchers agree that it’s most common between the ages of 20 and 45. It can be localized or generalized throughout the body.
- Solar urticaria: Similar to the previous type, only this time there’s direct exposure to the sun’s rays. Widespread cases have been reported, but outbreaks are more frequent in areas that have been exposed to sunlight.
- Delayed pressure urticaria: This develops when the skin is pressed for several minutes or hours. For example, when sitting down for a long time. There doesn’t need to be friction for symptoms to appear.
- Factitious urticaria: According to the American Osteopathic College of Dermatology (AOCD), this can affect up to 5% of the population. It’s also known as dermatographism and isn’t usually accompanied by itching. It can develop together with other types of hives.
3. Other types of hives
In the company of the types of urticaria we’ve already mentioned, dermatologists distinguish others that they can’t group into these categories. We highlight the following:
- Aquagenic urticaria: This is caused by contact with water, either in the workplace or because people shower excessively during the day. In rare cases, it can be generated by sweat.
- Contact urticaria: This is very similar to contact dermatitis. In fact, it’s sometimes very difficult to determine the difference between the two manifestations. The main characteristic is that the patient doesn’t develop allergic symptoms, only a rash.
- Exercise-induced urticaria: This is a rare variant in which patients manifest symptoms after performing any type of physical activity. Studies indicate that it can sometimes be accompanied by anaphylactic reactions, without having found a clear relationship between the two conditions.
- Cholinergic urticaria: In this case, the rashes appear after an increase in body temperature. Fever, heat, physical activity, hot showers, friction, stress, or spicy foods, among other factors, can cause this type of hives.
Some variants can’t be easily distinguished from others, so we urge you to seek medical assistance to start treatment and follow suggested lifestyle changes designed to correct the manifestations.
Sometimes the causes may be related to allergic reactions, so your doctor may choose to rule out various allergens during diagnosis. In the case of types of hives with specific catalysts, you should avoid related activities in order to prevent outbreaks from interrupting your day-to-day life.