When should I be worried about itchy hives
Hives (Urticaria)
What are hives?
Hives, or urticaria, are flat red welts that can appear anywhere on the skin and usually itch. Hives often occur as an allergic reaction to something eaten or something that has contacted the skin. Foods, medicines, and plants are common causes, but sun exposure, stress, infections, and autoimmune diseases have also been known to cause hives.
Symptoms include an itchy, stinging pink rash of slightly swollen skin. The rash may wax and wane in severity. Acute hives typically resolve within six weeks, but chronic hives (urticaria) can persist for months or years.
Hives often resolve on their own, especially in children. Otherwise, treatment for acute hives involves oral antihistamine medications to help relieve the itching and stinging. Chronic hives that do not improve with antihistamines may be treated additionally with corticosteroids, antibiotics, and other stronger medicines. A study found that 35% of people with chronic hives, are symptom free within one year, with another 29% having some reduction of symptoms.
You can safely treat this condition on your own as long as you does not develop trouble breathing. Any antihistamine (like Zyrtec, Clarinex, etc) works.
Hives and angioedema
Overview
Hives
Hives
Illustration of hives on different skin colors. Hives can cause swollen, itchy welts. Hives is also called urticaria.
Angioedema
Angioedema
Illustration of angioedema on different skin colors. Angioedema causes swelling in the deeper layers of skin, often of the face and lips. It often goes away within a day.
Hives also known as urticaria (ur-tih-KAR-e-uh) is a skin reaction that causes itchy welts that range in size from small spots to large blotches. Hives can be triggered by many situations and substances, including certain foods and medications.
Angioedema can arise with hives or alone. It causes swelling in the deeper layers of skin, often around the face and lips. Short-lived (acute) hives and angioedema are common. Most times, they are harmless, clear up within in a day and don't leave any lasting marks, even without treatment. Hives that last longer than six weeks are called chronic hives.
Hives and angioedema are usually treated with antihistamine medication. Angioedema can be life-threatening if swelling of the tongue or in the throat blocks the airway.
Symptoms
Hives
The welts associated with hives can be:
- Skin-colored, reddish on white skin, or purplish on black and brown skin
- Itchy, ranging from mild to intense
- Round, oval or worm-shaped
- As small as a pea or as large as a dinner plate
Most hives appear quickly and go away within 24 hours. This is known as acute hives. Chronic hives can last for months or years.
Angioedema
Angioedema is a reaction similar to hives that affects deeper layers of the skin. It can appear with hives or alone. Signs and symptoms include:
- Welts that form in minutes to hours
- Swelling, especially around the eyes, cheeks or lips
- Mild pain and warmth in the affected areas
When to see a doctor
You can usually treat mild cases of hives or angioedema at home. See your health care provider if your symptoms continue for more than a few days.
If you think your hives or angioedema was caused by a known allergy to food or a medication, your symptoms may be an early sign of an anaphylactic reaction. Seek emergency care if you feel your tongue, lips, mouth or throat swelling or if you're having trouble breathing.
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Causes
For most people who experience acute hives and angioedema, the exact cause can't be identified. The conditions are sometimes caused by:
- Foods. Many foods can trigger reactions in people with sensitivities. Shellfish, fish, peanuts, tree nuts, soy, eggs and milk are frequent offenders.
- Medications. Many medications may cause hives or angioedema, including penicillins, aspirin, ibuprofen (Advil, Motrin IB, others), naproxen sodium (Aleve) and blood pressure medications.
- Airborne allergens. Pollen and other allergens that you breathe in can trigger hives, sometimes accompanied by upper and lower respiratory tract symptoms.
- Insect bites and infections. Other causes of acute hives and angioedema are insect bites and infections.
Risk factors
Hives and angioedema are common. You may be at increased risk of hives and angioedema if you:
- Have had hives or angioedema before
- Have had other allergic reactions
- Have a family history of hives, angioedema or hereditary angioedema
Complications
Severe angioedema can be life-threatening if swelling of the tongue or in the throat blocks the airway.
Prevention
To lower your likelihood of experiencing hives or angioedema, take the following precautions:
- Avoid known triggers. If you know what has triggered your hives, try to avoid that substance.
- Bathe and change your clothes. If pollen or animal contact has triggered your hives in the past, take a bath or shower and change your clothes if you're exposed to pollen or animals.
Oct. 27, 2023
Healthdirect Free Australian health advice you can count on.
Key facts
- Hives, also known as 'urticaria' or 'nettle rash', is a skin rash that can occur for a range of reasons, including allergies, medicines or infections.
- A hive rash looks like red or skin-coloured raised bumps or welts on the skin, which are usually itchy.
- A hives rash is caused when the body produces a substance called histamine, which is released by the body in response to a perceived threat.
- Hives is diagnosed clinically, meaning that your doctor can diagnose the rash by talking to you and looking at your rash.
- The rash usually resolves on its own, but if a hives rash continues or get worse, antihistamines can help relieve the symptoms.
What is hives?
Hives is also known as 'urticaria' or 'nettle rash'. This skin rash can have a range of triggers, most commonly an allergic reaction. Other triggers include medicines or infections. Sometimes the trigger is unknown.
What are the symptoms of hives?
The hives rash looks like raised bumps or welts on the skin that are usually itchy, but may also sting. These can be red or skin-coloured. The raised areas of skin are known as wheals.
Patches of hives often join together to form larger swollen patches or urticaria. The affected area of skin can vary in size from quite small to about as large as a dinner plate. The patches of hives often join together to look like larger swollen patches of urticaria.
The hives rash can last for a few minutes to hours, and usually disappears within 24 hours. In rare cases, the rash can last for weeks.
CHECK YOUR SYMPTOMS Use the Symptom Checker and find out if you need to seek medical help.
What causes hives?
A hives rash is caused when your body produces a substance called histamine. This is a protein released by the body in response to a perceived threat (trigger).
In most cases, it is not known what triggers this reaction. Sometimes, urticaria can occur in response to:
Other triggers may include:
- cold air or water
- heat or sunlight
- vibration
- scratching
- sweating
- certain foods and drinks, such as spicy food, alcohol or coffee
In children, hives can be caused by a viral infection. This is why they sometimes go together with a cold or diarrhoea.
Hives that lasts for days at a time are almost never due to an allergy, apart from some cases of medicine allergy.
Stress rarely causes hives, but stress can make the symptoms worse.
When should I see my doctor?
You should see you doctor if you have a rash that looks like hives.
Some people have hives that don't go away or recur on a frequent basis. This is known as chronic urticaria. See your doctor if you have hives that keep coming back.
If you have taken antihistamines for your hives but they do not control the symptoms, discuss alternative treatment options with your doctor.
If your baby gets hives repeatedly, it's important to see your doctor. This could indicate an allergy to something they are frequently fed, such as cow's milk.
Sometimes hives can last for a long time. If you have hives for more than 6 weeks, your doctor may refer you for more tests to check if an underlying infection or chronic immune disorder is causing the symptoms.
FIND A HEALTH SERVICE The Service Finder can help you find doctors, pharmacies, hospitals and other health services.
How are hives diagnosed?
Hives is diagnosed clinically. Your doctor can diagnose the rash by talking to you and looking at your rash.
How are hives treated?
Hives usually resolve on its own without treatment. However, if the hives rash continues or gets worse, it can be treated with antihistamines. You can buy antihistamines over the counter at pharmacies.
Ask your pharmacist for advice on which antihistamine to take, as some will cause drowsiness, and can be taken at bed time if your rash is itchy and keeping you awake at night. Other antihistamines are not likely to cause drowsiness, so you can take them before driving or going to work or school.
To search medicines by active ingredient or brand name, use the healthdirect Medicines search feature.
Can hives be prevented?
If your hives are caused by a specific trigger, such as a food or medicine, you should avoid your known triggers.
Since most people don't know what caused their hives, it can be difficult to prevent.
Resources and support
For more information about the causes and management of hives see the Australasian Society of Clinical Immunology and Allergy website.
The Royal Children's Hospital has a fact sheet on hives for parents to learn about care at home and more severe reactions.
You can also call healthdirect on 1800 022 222 at any time to speak to a registered nurse (known as NURSE-ON-CALL in Victoria) for more information and advice.
When to Seek Help for Hives
Hives are typically harmless, but you may need to see a doctor if theyre severe, they wont go away, or they keep coming back. A doctor can help you treat and prevent hives.
Hives (urticaria) are itchy, raised patches or bumps that can erupt on any area of your body. Hives can also occur in mucous membranes, such as the inside of your mouth or under your eyelids.
Hives can make you uncomfortable, but they dont usually indicate a serious health problem. But there are times when hives should be brought to a doctor or other healthcare professionals attention.
In this article, well provide information about the causes of hives and go over typical symptoms. Well also clarify the instances when seeking medical attention for hives is important.
Hives occur when your immune system releases a chemical called histamine. Histamine is a chemical your body releases when it perceives a threat, such as an allergen.
The main symptom of hives is intense itchiness. Your skin may also feel warm to the touch or have a burning sensation.
The size, shape, and overall appearance of hives varies. They may be large, raised welts or tiny, raised pinpoint bumps. You may have one single hive, a small rash of multiple hives, or a very large rash that covers a significant area of skin.
Your skin tone may also affect the appearance of hives. Hives on paler skin tones are often pink or red in color. If you have light skin and press down on a hive, the discoloration will temporarily disappear (blanch).
Hives on black or brown skin may not take on a different color than the surrounding area of skin.
Mild hives arent usually serious. Mild or occasional hives dont typically necessitate a trip to the doctor. But you should consider mentioning your hives during your next doctors appointment.
If your hives are more severe, it may be time to talk with a doctor or other healthcare professional. Here are some factors to consider:
Timing
You should consider talking with a doctor or other healthcare professional if your hives last longer than a few days. Hives typically go away on their own. They may come and go for a few days and look different at different times.
If your hives are consistent and wont go away, something else may be going on.
If you recently started a new medication or supplement, you may be having an allergic reaction to it. Tell a doctor whats happening as soon as possible and call 911 or local emergency services if you develop any other symptoms, like fever or shortness of breath.
Allergic reactions to medication can happen within hours of starting a new medication. But they can also happen days or weeks later.
If your hives are recurrent, showing up every few days or weeks, you may benefit from seeing a specialist such as a dermatologist or an allergist.
It can be hard to uncover the cause of hives. You could be having a reaction to anything you regularly come into contact with, such as soaps, foods, or pets.
An allergist may recommend allergy testing to help you identify the triggering allergen.
Response to treatment
In some instances, over-the-counter (OTC) treatments such as antihistamines or topical corticosteroids may not provide enough relief.
If your hives arent responding to treatment, you may want to speak with a doctor or other healthcare professional. They can offer additional treatments, such as prescription allergy medications and injections.
Triggers
Hives have many potential triggers, including:
It can be challenging to determine whats triggering your hives. You can talk with an allergist about allergy tests that can help you identify the offending substances.
Allergy tests are particularly helpful for things you come into contact with regularly, like foods, pollen, and bug bites. Once you identify your triggers, you can work to avoid them in the future.
Severity
Hives range in severity from mild to severe. If your hives are accompanied by swelling or pain, it may be time to speak with a doctor or other healthcare professional. The same is true for hives that are extremely itchy.
Hives covering a large body area, such as the entire torso, may also warrant a discussion with a doctor or other healthcare professional.
There are times when hives may be a symptom of a medical emergency, such as:
Anaphylaxis
Anaphylaxis is a severe allergic reaction often accompanied by hives and angioedema. Other symptoms include wheezing, swelling, and shortness of breath.
If you or someone else has anaphylaxis symptoms, call 911 or local emergency services. If you have an EpiPen (epinephrine medication), use it immediately.
Angioedema
In some instances, hives may be accompanied by deep, painful swelling within the skin or mucous membranes (angioedema).
The swelling caused by angioedema can occur in these areas:
- under eyelids and around the eyes
- on the lips, mouth, and throat
- beneath the skin
Angioedema can make it hard to breathe and can quickly become a medical emergency. Angioedema is common during anaphylaxis.
Alpha-gal syndrome
Hives can sometimes be a symptom of alpha-gal syndrome, a medical emergency that requires immediate treatment. Alpha-gal syndrome is an allergic reaction to alpha-gal, a sugar molecule found in:
- red meat, including beef, pork, venison, and lamb
- gelatin, including gelatin-coated medications, cosmetics, and foods such as candy
- dairy products, including cows milk
- bites from lone star ticks and possibly, other types of ticks
Its also known as the red meat allergy. It can develop in adults who have been bitten by a lone star tick.
Alpha-gal syndrome is usually accompanied by symptoms such as:
- nausea and vomiting
- diarrhea
- indigestion
- heartburn
- stomach pain
A doctor will examine your skin to assess whether you have hives or a different condition, such as dermatitis or eczema.
A doctor will ask you about your medical history, your symptoms, and how severe they have been. Theyll want to know how often you get hives, how long they last, and any potential triggers you suspect.
You may undergo diagnostic tests, such as blood work or a skin biopsy, to rule out underlying illnesses or infections such as ringworm.
Allergy tests, such as a skin prick test, can help you identify your triggers. For this test, a doctor will insert a variety of potential allergens under your skin to see if any elicit an allergic reaction.
If youre able to identify your triggers, eliminating those substances will be an important part of treatment.
In some instances, alleviating anxiety and stress may also be helpful. A doctor or other healthcare professional may recommend medication or stress-reducing activities, like meditation, yoga, and therapy.
A healthcare professional may recommend prescription-strength oral antihistamines, such as Clarinex (desloratadine). Prescription-strength hydrocortisone cream may also help treat reoccurring hives and reduce itching.
Depending on the severity of your condition, a doctor or other healthcare professional may recommend allergy shots. Allergy shots are a long-term treatment option used to decrease your sensitivity to allergens in your environment. But the treatment schedule is time-intensive and can often last for years.
Allergy shots may be beneficial if you have severe hives or hives caused by unavoidable allergens. This treatment isnt used for hives caused by food allergies.
Mild hives often respond quickly to OTC antihistamines. There are several types of antihistamines, and they can be taken by mouth or applied to the skin. They work by reducing the effects of histamine.
There are many different brands of antihistamines you can choose from. Some cause marked drowsiness, dry mouth, and other symptoms. Read the label so you know what to expect before you buy.
Topical steroid creams can also be beneficial for reducing swelling and itching. These medications work by constricting blood vessels and reducing inflammation.
To prevent, alleviate, or reduce the symptoms of hives, you can try these at-home remedies:
- remove potential triggers and allergens from your environment
- use sun protection such as sunscreen or sun-protective clothing
- avoid wearing tight or restrictive clothing
- place cool compresses on the affected areas of skin
- avoid scratching itchy skin
- take a colloidal oatmeal bath or use colloidal oatmeal lotion on the affected area
- treat the skin with witch hazel or calamine lotion
Hives usually dissipate within a few days or faster with at-home treatments.
In some instances, hives may require medical treatment. A doctor or other healthcare professional may prescribe oral medications or recommend allergy injections if you have long-term, severe, or recurring hives.
