What is urticaria (hives)?

Urticaria, also commonly known as “hives,” is characterized by the appearance of papules (large red, swollen patches) that itch and can appear anywhere on the body. It can go away quickly, or it can dissipate in one place and reappear in other parts of the body.

This inflammatory skin condition is not a disease, but rather a symptom, and is completely benign. In fact, more than one in five people will experience hives at least once in their lifetime.

It is nevertheless interesting to know the causes, symptoms, treatments and the most effective prevention methods known to date.

You can read more about urticaria in this article and the best practices to follow if you suspect it is occurring.

Causes and triggers

Urticaria almost always occurs as a reaction to an external irritant that has been ingested or has come into contact with the skin.

More specifically, when an irritant is detected by the immune system, it secretes biogenic amines (such as histamine) that cause inflammation and itching.

Among the most common irritants are:

• Insect bites
• Exposure to chemicals
• Exposure to cold or intense heat
• Mental health problems (anxiety, depression, etc.)
• Food allergies (food, supplements or medications)
• Dermatological allergies

Here are some other triggers that are commonly associated with hives:

The end of pregnancy

It is common for women to be more prone to hives towards the end of their pregnancy. It is believed that it is due to hormonal reasons. Also, tight skin seems to be more vulnerable to external irritants.

Swimming

While many believe that products, such as chlorine are the source of swimmers' urticaria attacks, it is said to be rather the prolonged exposure to water of a temperature colder than that of the body - the same way as exposure to unusual cold can cause papules to appear.

Friction

It is not uncommon for hives to appear on a person’s skin from being rubbed, such as by rough clothing, or by scratching the skin.

Pressure

A known source of localized hives is from the pressure of elastic bands in pants or underwear, camisole straps or bras.

Disease

More rarely, diseases, such as rheumatoid arthritis, hypothyroidism and hyperthyroidism, as well as other conditions predispose the person to possible urticaria attacks.

Types of hives

There is more than one kind of hives. However, they are grouped under three main categories:

• Acute urticaria
• Chronic urticaria
• Recurrent hives

So it's important to stay tuned for signs that lead to attacks, especially if they’re recurring and you can't quite put your finger on the irritant.

A healthcare professional, such as your pharmacist can help you ask the right questions, and if necessary, refer you to your doctor for relief options.

Acute urticaria

Acute urticaria is the most common form of urticaria seen, due to factors regularly observed, such as taking a new medication, an insect bite, emotional stress or ingesting a food rich in histamines like shellfish, tropical fruit, egg whites, different kinds of fish, and more.

Acute hives can last from a few minutes to a few hours. They also tend to reappear sporadically in the days that follow.

Chronic urticaria

Unlike acute urticaria, chronic urticaria tends to progress over a longer period of time, for more than six consecutive weeks. It is very rarely allergic in nature, and has regular attacks and signs that appear from episode to episode.

Recurrent urticaria

If a recurrence is observed, but the episodes become less frequent, it is called recurrent urticaria. Unlike the other types of urticaria mentioned above, this form is more difficult to attribute to an environmental irritant, food or any other external stressor. To date, we do not know what causes recurrent urticaria.

How is urticaria diagnosed?

If you're having a sudden urticaria attack and have never had it before, chances are you've come into contact with a potential irritant.

Your doctor will try to determine the triggering factor through a series of questions relating to when the papules appeared. You will be asked if you have introduced a new food to your diet, if you are using a new detergent, if you are taking a new medicine, etc.

Although the goal is to identify a trigger, the fact remains that 50% of urticaria episodes go without explanation.

In cases of chronic or recurrent urticaria, your doctor will often refer you to specialists, such as allergists and dermatologists who will further investigate.

Treatment

No solution is yet available on the market to specifically treat urticaria. The good news is that all types of hives eventually go away.

On the other hand, since seizures are mainly due to exposure to an external irritant, prevention is by far the best solution to treat urticaria. However, this option remains valid only if you’re aware of the irritant in question... which is usually a mystery.

Fortunately, itching and patches can be relieved with medications like antihistamines. However, some of these drugs on the shelves can cause marked drowsiness. It is therefore important to consult your pharmacist for less drowsy solutions that can be just as effective.

Topical application of corticosteroids can also be effective to soothe itching. However, this solution is not recommended in the long term because of the side effects of prolonged exposure to corticosteroids. It is best to consult a healthcare professional before using them.

When should you consult your doctor?

It’s a good idea to see your doctor when the signs worsen or persist, and the options for relieving the itching are unsatisfactory.

Health professionals near you, such as your pharmacist, can also guide you on the next steps to take to ensure your well-being!