Most people have had hives at some point: itchy, raised welts that appear after a new food, a medicine or an insect bite, then fade within a day or two. For some adults, though, the welts keep coming back for weeks or months with no obvious reason. This is chronic urticaria, and chronic hives in adults can be exhausting, disrupting sleep, work and confidence. This guide explains what chronic hives are, the common types and triggers, how treatment usually works, and when to see a doctor in Singapore.
This article is general information, not medical advice. Please see a doctor for diagnosis and treatment.
What Counts as Chronic Hives
Hives (the medical term is urticaria) are raised, itchy welts on the skin, sometimes called wheals. They can be pink or red on lighter skin and may look skin-coloured or darker on deeper skin tones. Individual welts usually fade within a day, but new ones can appear elsewhere.
Doctors generally call hives chronic when they come and go on most days for six weeks or longer. Hives that clear up sooner are called acute. Acute hives often have a clear trigger, such as a food allergy, a drug reaction or an infection. Chronic hives in adults are different: in many cases, no external allergen is found at all.
Some people also experience angioedema, which is deeper swelling of the skin, often around the eyes, lips, hands or feet. Angioedema can happen with or without the welts.
If you are looking for information on children, see our separate guide on hives and urticaria in children.
The Main Types and Common Triggers
Chronic urticaria is usually divided into two broad groups. Knowing which one you have helps your doctor plan treatment.
| Type | What happens | Common examples |
|---|---|---|
| Chronic spontaneous urticaria | Hives appear on their own with no consistent outside trigger | Daily or near-daily welts, sometimes with angioedema |
| Dermographism | Welts form where skin is scratched or rubbed | Lines appearing after scratching, tight straps or towelling |
| Cold or heat urticaria | Hives after temperature changes | Air-conditioned rooms, cold drinks, swimming pools, hot showers |
| Cholinergic urticaria | Small itchy bumps when body temperature rises | Exercise, sweating, spicy food, emotional stress |
| Pressure urticaria | Delayed swelling where pressure was applied | Bag straps, waistbands, sitting for long periods |
The second to fifth rows are forms of chronic inducible urticaria, where a physical trigger reliably sets off the hives. Some people have more than one type.
Chronic spontaneous urticaria is thought to involve the immune system in many people. In some cases, the body produces antibodies that activate mast cells in the skin, which release histamine and cause the welts. It is not contagious, and it is usually not a sign of a hidden allergy to a food you eat every day.
Even when the root cause is unclear, several factors can make flares worse:
- Certain painkillers, particularly some anti-inflammatory medicines, can aggravate hives in some people. Ask your doctor or pharmacist before taking them.
- Infections, such as a cold or other viral illness.
- Stress and poor sleep, which many people notice worsen their symptoms.
- Heat and sweating, which is very relevant in Singapore’s humid climate.
- Alcohol, which some people find triggers or worsens flares.
- Tight clothing, if you have a pressure or rubbing component.
Some people also have thyroid conditions or other autoimmune conditions alongside chronic hives, which is one reason doctors may suggest blood tests.
How Chronic Hives Are Diagnosed
There is no single test that diagnoses chronic urticaria. Your doctor will mostly rely on your history and what the hives look like. Expect questions about:
- How long the hives have been happening and how often.
- How long each welt lasts. Welts that last more than a day or leave bruising may need further checks.
- Any swelling of the lips, eyes or throat.
- Medicines, supplements and recent infections.
- Whether physical triggers like scratching, cold or exercise set them off.
Doctors may order basic blood tests, and sometimes a skin challenge test for inducible types. Extensive allergy testing is not always needed for chronic spontaneous urticaria, because food allergies rarely explain daily hives lasting months. Your doctor will decide what is appropriate.
A useful thing to bring is a symptom diary or photos. Hives can disappear by the time you reach the clinic, so pictures on your phone with dates and notes on what you ate, did and felt are very helpful.
Treatment Options: From Antihistamines to Specialist Care
The goal of treatment is to control symptoms so you can live normally while the condition runs its course. Chronic hives often settle on their own over time, though how long this takes varies a lot from person to person.
- Non-drowsy antihistamines. Modern, less sedating antihistamines taken regularly are the usual first step. They block histamine, which drives the itch and welts. Your doctor may advise taking them daily rather than only when a flare appears.
- Adjusting the dose under supervision. If standard doses do not give enough control, doctors sometimes increase the dose. Do not do this on your own. Only change how you take any medicine on your doctor’s advice.
- Short courses of other medicines. For severe flares, doctors occasionally prescribe a short course of oral steroids. These are not suited to long-term use because of side effects.
- Biologic treatment. For chronic spontaneous urticaria that does not respond to antihistamines, specialists may consider an injectable biologic medicine. This is usually prescribed and monitored by a dermatologist or immunologist.
- Other immune-modulating medicines. In a smaller group of patients, specialists may consider other treatments that calm the immune system, with regular monitoring.
Alongside medicines, simple habits help:
- Wear loose, breathable cotton clothing.
- Take lukewarm rather than hot showers, and pat skin dry.
- Use a gentle, fragrance-free moisturiser and soap.
- Keep fingernails short to reduce damage from scratching.
- Keep a cool fan or air-conditioning on at night if heat sets you off, unless cold is your trigger.
Getting Care in Singapore
You can start with a general practitioner (GP) or a polyclinic. Many people with chronic hives in adults are well managed in primary care. If your hives are not controlled, keep returning, or come with frequent angioedema, your doctor can refer you to a dermatologist or an allergy and immunology specialist.
For subsidised specialist care at a public hospital or the National Skin Centre, you will usually need a referral from a polyclinic or a GP under the CHAS scheme (the Community Health Assist Scheme, which helps eligible residents with outpatient costs). Check current referral routes and subsidy details with your polyclinic, the specialist centre or HealthHub, as arrangements can change.
Living with chronic itch can affect mood and sleep. If it is wearing you down, tell your doctor. Our guides on understanding inflammation and your health and coping with chronic pain have practical ideas for managing long-term conditions day to day.
When to Seek Urgent Help
Most hives are uncomfortable but not dangerous. Call 995 or go to an emergency department immediately if hives come with any of the following:
- Swelling of the tongue, throat or lips that affects breathing or swallowing.
- Wheezing, tightness in the chest or difficulty breathing.
- Feeling faint, dizzy, or a racing heartbeat.
- Vomiting or severe stomach pain alongside the rash.
These can be signs of anaphylaxis, a severe allergic reaction that needs emergency treatment. If you have been prescribed an adrenaline auto-injector, use it as instructed and still seek emergency care.
Chronic hives can feel endless, but with the right diagnosis and a treatment plan worked out with your doctor, most adults find their symptoms become much more manageable.
Frequently Asked Questions
Do chronic hives mean I have a hidden food allergy? Usually not. Chronic spontaneous urticaria is often not linked to an external allergen, and food allergies rarely explain daily hives lasting months. Extensive allergy testing is not always needed, so let your doctor decide which tests are appropriate.
How long do chronic hives usually last? It varies a lot from person to person. Chronic hives often settle on their own over time, and treatment aims to control symptoms while that happens. Doctors call hives chronic when they come and go on most days for six weeks or longer.
Can heat and sweating in Singapore make hives worse? Yes, for many people. Heat, sweating, stress, poor sleep, infections and alcohol can worsen flares, and cold or heat can trigger inducible types. Loose cotton clothing, lukewarm showers and a cool bedroom may help.
Which painkillers can aggravate chronic hives? Certain painkillers, particularly some anti-inflammatory medicines, can aggravate hives in some people. Ask your doctor or pharmacist before taking any, and only change how you take a medicine on your doctor’s advice.
When do chronic hives need a specialist instead of a GP? See a dermatologist or allergy and immunology specialist if hives are not controlled, keep returning or come with frequent angioedema. Subsidised specialist care usually needs a referral from a polyclinic or CHAS GP. Call 995 for lip, tongue or throat swelling or breathing trouble.
Official sources: HealthHub
Further reading: Itchy Skin in Older Adults: Causes and Relief · Vitiligo in Singapore: Treatment and Coverage Options