Urticaria (Hives): Causes, Relief and When to Worry

Urticaria, commonly called hives or pitti, is an itchy rash of raised, swollen welts that appear suddenly and usually fade within 24 hours, often to reappear elsewhere. Most episodes are short lived and settle with non-drowsy antihistamines, but hives that come with swelling of the tongue or throat, wheezing or faintness need emergency care.

Hives are very common, and around one in five people will have them at some point in life. They can be frightening, especially when the whole body is covered overnight. The good news is that urticaria is usually harmless and very treatable, even when it lasts for months.

What do hives look like?

• Raised welts (wheals) that are pink, red or skin coloured. On brown skin they may look skin coloured or slightly darker, with less obvious redness.
• Intense itching, sometimes burning or stinging.
• Shapes and sizes that change, from small dots to large, joined patches.
• Individual welts that fade within 24 hours without leaving a mark.
• Angioedema in some people: deeper swelling of the lips, eyelids, hands, feet or genitals, which can last a day or two and tends to feel more painful than itchy.

If a single spot lasts more than a day or two, leaves a bruise or dark mark, or is painful rather than itchy, it may be a different condition called urticarial vasculitis, which needs a dermatologist’s assessment.

What is the difference between acute and chronic urticaria?

Feature	Acute urticaria	Chronic urticaria
Duration	Less than 6 weeks	Hives on most days for more than 6 weeks
Common triggers	Viral infections, medicines, foods, insect stings	Usually no external cause found. Often autoimmune
Allergy tests	Sometimes helpful if a trigger is suspected	Rarely needed for most people
Outlook	Usually settles within days to weeks	Often improves over months to years

What causes acute hives?

Acute hives often have an identifiable trigger, such as:

• Viral infections, including common colds, especially in children
• Medicines, such as painkillers (NSAIDs like aspirin, ibuprofen and diclofenac) and some antibiotics
• Foods, such as nuts, shellfish, fish, eggs and milk in those who are allergic
• Insect bites and stings
• Contact with certain plants, latex or animals

Often, though, no clear trigger is found, even for acute hives.

What causes chronic hives?

In chronic spontaneous urticaria, hives appear without an external trigger. In many people the immune system produces antibodies that activate mast cells in the skin, releasing histamine. It is more common in people with autoimmune thyroid disease.

Things that can make chronic hives worse include:

• NSAID painkillers
• Alcohol
• Stress
• Infections
• Heat, tight clothing and pressure

What are physical or inducible hives?

Some people get hives from a specific physical trigger:

• Dermographism: welts where the skin is scratched or rubbed. Writing on the skin with a fingernail leaves a raised line.
• Cholinergic urticaria: tiny itchy bumps with heat, sweating, exercise, hot baths or spicy food. Common in India’s hot summers.
• Cold urticaria: hives after cold water, air conditioning or cold drinks.
• Pressure urticaria: deep swelling hours after pressure from bags, waistbands or sitting.
• Solar urticaria: hives within minutes of sun exposure.

How are hives treated?

Treatment aims to control symptoms while the condition settles. Your dermatologist may consider:

• Second generation, non-drowsy antihistamines taken regularly, which Indian and international guidelines recommend as first line treatment. Taking them every day, rather than only when hives appear, often works better for chronic urticaria. Your doctor may adjust the dose if standard treatment is not enough.
• Avoiding identified triggers, such as a particular painkiller.
• Biologic injections (such as omalizumab) for chronic urticaria not controlled with antihistamines.
• Other immune modulating medicines, such as ciclosporin, in selected cases under specialist monitoring.
• Short courses of oral steroids only for severe acute flares, under supervision.

A cautionary note: in India, repeated steroid injections for hives are common. They work quickly but do not cure urticaria, and repeated use can cause weight gain, high blood sugar, bone thinning, raised blood pressure and other serious effects. Steroid creams do not help hives and should not be applied for them. See our article on topical steroid misuse.

What tests might be needed?

Most people with acute hives do not need tests. For chronic urticaria, your dermatologist may consider limited tests such as a blood count, inflammation markers and thyroid tests. Extensive allergy panels are usually not helpful unless your history points to a specific trigger.

What can I do at home for relief?

• Take antihistamines as advised.
• Apply cool compresses, or take a cool shower.
• Wear loose, soft cotton clothing.
• Avoid hot baths, alcohol and NSAID painkillers if they make your hives worse. Ask your doctor about safer pain relief.
• Use calamine or a simple soothing moisturiser for itch.
• Keep a diary of foods, medicines, activities and stress if hives keep coming back.
• Avoid scratching, which releases more histamine.

Are hives common in children, and is stress a trigger?

Hives are common in children and are most often triggered by viral infections rather than food. A child who develops hives during a cold or fever usually improves as the infection settles. Food related hives in children tend to appear within minutes to two hours of eating the food, often with lip swelling or vomiting, which is a pattern worth noting and discussing with your doctor.

Stress does not usually cause urticaria on its own, but many adults notice that chronic hives flare during exams, deadlines, family events or poor sleep. Managing stress will not cure urticaria, yet it can make flares less frequent and easier to control alongside medical treatment.

In India, people are sometimes told that hives come from heat in the body or from particular foods like brinjal or prawns. Unless you have a clear, repeated reaction to a specific food, there is no need to follow restrictive diets.

Is it hives or another itchy rash?

Hives are different from eczema, which is a dry, scaly, longer lasting rash; see our eczema guide. Ring shaped itchy patches that last for weeks are more likely fungal; see ringworm in India. Pinpoint itchy bumps after sweating may be prickly heat rather than hives.

When to see a dermatologist

Seek emergency care immediately if hives come with:

• Swelling of the tongue, throat or face
• Difficulty breathing, wheezing or a tight chest
• Difficulty swallowing or a hoarse voice
• Dizziness, fainting or a rapid heartbeat
• Vomiting or abdominal pain after a sting, food or medicine

Book a dermatology review if:

• Hives last more than six weeks or keep coming back.
• Antihistamines do not control your symptoms.
• Individual welts last more than 24 hours or leave bruising.
• You have frequent lip or eyelid swelling.
• Hives come with fever, joint pain or feeling unwell.
• You have been given repeated steroid injections and want a safer long term plan.

Chronic hives can be tiring, but most people achieve good control. Dr. Maria offers online consultations to help work out the pattern, review your medicines and set up a treatment plan you can follow.