Urticaria (Hives): Causes, Diagnosis, and Current Treatment

What is urticaria?

Urticaria, commonly known as hives, is a skin condition characterized by sudden, itchy, raised red patches (urticaria plaques/wheals), angioedema, or both.

Urticaria is primarily a disease in which mast cells play a role. This is also how it is defined in the current 2026 international guidelines.

One of the most important points is this:

Hives are not always an allergy.

In chronic spontaneous urticaria, which recurs particularly over weeks or months, most patients are not caused by a single food or external allergen.

Briefly, what you need to know

Urticaria plaques are usually intensely itchy.

A single urticaria plaque usually disappears without a trace within 24 hours; new ones may appear in other areas.

Angioedema is the term used when more severe swelling develops in areas such as the lips and eyelids.

Urticaria lasting less than 6 weeks is classified as acute, while urticaria lasting longer than 6 weeks is classified as chronic.

Chronic urticaria has spontaneous and inducible types.

Chronic spontaneous urticaria is usually not a classic food allergy.

The goal of treatment is to bring the patient's symptoms under as complete control as possible.

What does urticaria look like?

Typical urticaria plaque:

raised from the skin,

pink or red,

intensely itchy,

different sizes and shapes,

temporary

It is a lesion.

One of its most characteristic features is its ability to move.

For example, a patient might wake up in the morning to find a large bump on their arm; a few hours later, that lesion might disappear, while new ones could appear on their back or leg.

This behavior is quite valuable in diagnosing urticaria.

What if a lesion lasts longer than 24 hours?

Same lesion:

If it stays in the same place for more than 24 hours,

If it causes pain/burning rather than itching,

if it leaves behind bruising and pigmentation

Other conditions such as urticarial vasculitis may need to be evaluated.

So not every rash that looks like hives is urticaria.

What is the difference between acute and chronic urticaria?

Acute urticaria

The total duration of symptoms is less than 6 weeks.

It can occur for a variety of reasons, including infections, medications, and certain allergic reactions.

Chronic urticaria

Chronic urticaria is defined as the recurrence of urticaria, angioedema, or both for more than 6 weeks.

We also divide chronic urticaria into two major groups:

Chronic spontaneous urticaria (CSU) occurs without a specific external physical stimulus.

Chronic inducible urticaria (CIndU) is triggered by specific stimuli such as cold, pressure, temperature, or dermographism.

This distinction is important for diagnosis and treatment.

Is chronic spontaneous urticaria an allergy?

Most of the time it is not in the classical sense.

This is one of the most common misunderstandings among patients.

For months:

“"What did I eat to cause this?"”

Thinking this way and constantly eliminating new foods from the diet can lead to unnecessary restrictions in patients with chronic spontaneous urticaria.

It is currently known that mast cells and various autoimmune mechanisms play a significant role in the pathogenesis of CSU. This field is still rapidly developing; the current pathogenesis study by Kocatürk and Berlin team, dated 2026, also addresses different endotypes of the disease and mast cell activation mechanisms.

What causes urticaria?

The answer to this question depends on the type of urticaria.

In acute urticaria:

infections,

some medications,

true allergic reactions

can play a role.

In chronic spontaneous urticaria, however, most often:

“"Let's find one reason and remove it from your life."”

There is no such simple mechanism.

Therefore, instead of performing dozens of random tests on a patient with chronic urticaria, a history-based, targeted examination is more appropriate.

Should every patient with hives undergo allergy testing?

No.

This will be one of the key distinguishing messages on our page.

In the absence of a clear history suggesting a food allergy, routinely performing comprehensive food panels in chronic spontaneous urticaria is generally not meaningful.

Current international guidelines also recommend keeping the diagnostic approach limited and targeted; further tests are selected according to the patient's history and findings.

“Urticaria → 50-item allergy panel”

That won't be our approach.

What is angioedema?

Angioedema is swelling that develops in the deeper layers of the skin.

Most frequent:

lips,

eyelids,

face,

hands and feet

It can be seen in regions such as these.

It may occur with urticaria, or in some patients it may appear without urticaria plaques.

Recurrent angioedema, especially without urticaria, may warrant investigation of different disease mechanisms.

When is it an emergency?

Swelling of the tongue or throat, difficulty breathing, voice changes, severe dizziness/impaired consciousness, or symptoms suggestive of a systemic allergic reaction require immediate medical attention.

Because here we may be talking not just about ordinary urticaria, but also about emergencies such as airway involvement or anaphylaxis.

Can urticaria be caused by stress?

Stress can worsen symptoms in some patients, but it can also worsen chronic urticaria:

“"It's due to stress."”

To explain it that way oversimplifies the biology of the disease.

Chronic spontaneous urticaria is a true mast cell-mediated disease, and it is not a condition where the patient psychologically "produces" the symptoms.

How is urticaria treated?

The current treatment approach is step-by-step.

1. Second-generation H1 antihistamines

The primary focus of first-line treatment is on newer generation, second-generation H1 antihistamines with low sedation potential.

The key point here is that the medications only:

“"Pick one when it itches."”

The reason is that using it in this way is not the right strategy for every patient with chronic urticaria.

Active chronic urticaria may require regular treatment.

2. Increasing the antihistamine dose

In chronic urticaria that cannot be controlled with standard doses, current guidelines recommend increasing the dose of second-generation H1 antihistamines up to four times if necessary.

This does not mean the patient should increase the dose on their own; treatment should be determined after a dermatological evaluation.

Should cortisone be used for urticaria?

Long-term systemic corticosteroid use is not a routine treatment for chronic urticaria.

Short-term use may be considered in certain severe acute exacerbations; however:

“"You have hives → get a cortisone injection → it will go away."”

This is not chronic disease management.

Because of the side effects of long-term corticosteroids, the goal of modern urticaria treatment is not to establish a steroid-dependent system.

What is omalizumab?

In chronic spontaneous urticaria that is not adequately controlled with standard antihistamine therapy, omalizumab has long been one of the primary biological therapies.

It acts via the anti-IgE mechanism.

The important point from the patient's perspective:

Treatment options for chronic urticaria that cannot be controlled with antihistamines are not exhausted.

The 2026 international guidelines and current clinical literature indicate that biological therapies continue to play a central role in the management of chronic urticaria.

What if omalizumab doesn't work?

Treatment options for chronic urticaria have been rapidly improving in recent years.

For patients who do not respond adequately to omalizumab, cyclosporine has long been one of the options in the guideline algorithm.

However, in recent years, the treatment landscape has expanded significantly with new biological drugs and small molecules targeting mast cell signaling pathways. The 2026 JAAD review also emphasizes that the chronic urticaria treatment landscape is rapidly changing with new biologics, small molecules, and mast cell-targeting therapies.

How do we know if the treatment was successful?

“"I itch a little less" isn't the only criterion.

In the field of urticaria, there are validated tools for measuring disease activity and control:

UAS7 — Urticaria Activity Score UCT — Urticaria Control Test

like.

The goal of modern treatment is not just to reduce symptoms, but to achieve as complete disease control as possible.

Will urticaria completely disappear?

Chronic spontaneous urticaria does not necessarily have to last a lifetime.

Many patients may experience spontaneous remission over time; however, it is not possible to predict precisely when this will occur at the individual patient level.

Because:

“"If you take the medication for six months, it will definitely go away."”

We will not provide timeframes like that.

The goal of treatment is to allow patients to continue living a normal life with as few symptoms as possible while the disease is active.

Frequently Asked Questions

Is hives contagious? No.

Is hives a food allergy? Some acute hives may be associated with an allergic reaction; however, chronic spontaneous hives are usually not a classic food allergy.

Do all patients need allergy tests? No. Tests should be selected based on history and clinical findings.

Can urticaria last for years? Yes. Chronic urticaria can persist for a long time in some patients; however, spontaneous remission can also occur.

Is it right to get cortisone injections? Long-term or repeated systemic cortisone is not the standard treatment for chronic urticaria.

Are antihistamines addictive? Second-generation antihistamines, as described in the guidelines, are not considered addictive drugs.

Is omalizumab a cancer drug? No. It is a biological therapy in the form of monoclonal antibodies targeting IgE and is used in certain diseases, including chronic spontaneous urticaria.

Selected Scientific Publications of Dr. Utkan Kızıltaç in the Field of Urticaria

• Kocatürk E, Kızıltaç U, Can P, et al. Validation of the Turkish version of the Urticaria Control Test: Correlation with other tools and comparison between spontaneous and inducible chronic urticaria. World Allergy Organ J. 2019;12(1):100009. PMID: 30937134. DOI: 10.1016/j.waojou.2018.11.007. https://pubmed.ncbi.nlm.nih.gov/30937134/

• Can PK, Etikan P, Kızıltaç U, et al. Fric Test Revisited: A Suggestion for a New Scoring System and Its Correlation with Urticaria Control Test and Dermatology Quality of Life Index. Int Arch Allergy Immunol. 2019;178(1):76-82. PMID: 30286461. DOI: 10.1159/000492970. https://pubmed.ncbi.nlm.nih.gov/30286461/

• Ornek SA, Alkilinc AS, Kızıltac U, Kızıltac K, Kocaturk E. Effect of Puberty, Menstruation, Pregnancy, Lactation, and Menopause on Chronic Urticaria Activity. J Cutan Med Surg. 2023;27(5):466-471. PMID: 37537974. DOI: 10.1177/12034754231191472. https://pubmed.ncbi.nlm.nih.gov/37537974/