What makes hives worse

9 Ways to Ease the Itch of Chronic Hives

They're itchy, red, and raised and often appear at the worst possible times. About 20 percent of the population will get them at least once in their lives, according to the American College of Allergy, Asthma & Immunology. They're hives. And hives that last more than six weeks are considered chronic (persistent or recurring). For some people, these hives are a result of allergies, but for others there's no discernible cause. Chronic hives with no known cause are called chronic idiopathic urticaria (hives).

The itching associated with these hives, which stems from the release of natural chemicals called histamines by your bodys immune system, can dramatically affect your quality of life. This is among the main findings of a study published in August 2015 in the journal Annals of Allergy, Asthma & Immunology. Still, there's a lot you can do to ease the itch of chronic hives.

Cholinergic Urticaria: Can Heat Cause Hives?

Hives are a skin reaction of itchy bumps that may burn or sting. They can develop not only from an immune response to an allergen but also to heat.

While you may think of hives or urticaria as resulting from an allergic reaction, they can also be caused by heat. These are called heat hives or cholinergic urticaria.

In some people, a rise in temperature can produce the chemical histamine, similar to what happens when your immune system fights allergies. Histamine dilates blood vessels and results in swelling.

There is limited research on cholinergic urticaria. The few available studies estimate a wide prevalence range of 0.6-11.2%.

If you notice hives tend to break out when your body temperature rises, it may be a sign that heat triggers your hives. Any exposure to heat could potentially trigger heat hives. This can include:

• bathing in warm or hot water
• being near a heat source like a stove
• being outdoors in the sun
• eating hot food

According to research from 2022, physical factors that can contribute to the development of heat hives include:

• being allergic to sweat
• clogged sweat ducts, lack of sweating
• medications or substances that affect the neurotransmitter acetylcholine

Although being allergic to sweat is rare, research shows that 66% of patients who get heat hives also have a histamine response against antigens in their sweat.

In rare cases, heat hives can sometimes be related to exercise-induced anaphylaxis. Seek immediate medical attention if this is the case. If you have an epinephrine injector (EpiPen), administer your medication while you wait for help to arrive.

Get step-by-step instructions on how to use an EpiPen.

Heat rash vs. hives

Heat hives share similar causes and symptoms with many forms of heat rash, also known as miliaria.

Heat rash can also be triggered by things like perspiration trapped under your skin by blocked pores. Causes also include humid weather, physical activity, or other factors that lead to a rise in the temperature of your body.

While heat rash tends to fade on its own, consider visiting your doctor for more severe or persistent cases. Your doctor can provide a proper diagnosis and help you determine whether youre experiencing hives or heat rash.

The symptoms of heat hives are similar to hives caused by other triggers such as insect bites, allergies, or medications.

Hives can appear as red, itchy welts ranging in size from less than half an inch up to several inches in diameter. Hives on darker skin tones may appear closer to the color of the skin.

Most cases of hives caused by heat appear within a few minutes after exposure and will subside within 1-2 hours. However, heat hives can also be accompanied by angioedema, which is swelling beneath the affected skin caused by leaking blood vessels.

In some cases, you can also experience other symptoms along with heat hives. These include:

• fatigue or weakness.
• faintness
• nausea
• diarrhea
• headache

You may be experiencing exercise-induced anaphylaxis if you also have the following symptoms:

• difficulty breathing
• wheezing
• abdominal pain
• nausea
• headache

Call 911 if you experience these symptoms. If you have an EpiPen, you should administer the medication while you wait for help to arrive.

If your symptoms arent severe but interfere with your lifestyle, see your doctor. A simple evaluation and conversation about your symptoms may be enough for them to diagnose heat hives.

Sometimes, your doctor may want to conduct tests to gather more information about the condition. These may include:

• A passive warming test: This will raise your body temperature with warm water or an increased room temperature. Your doctor can observe your bodys reaction when exposed to increased heat.
• A methacholine skin challenge test: Your doctor may inject a medication called methacholine into your body and observe for a reaction. However, not everyone with heat hives gets a positive result, so the doctor may use this test in combination with others.
• An exercise challenge test: Your doctor will have you exercise and watch for symptoms of CU. You may also be measured with other medical instruments during the test.

You should see a doctor immediately if you suspect you have exercise-induced anaphylaxis, which must be attended to as soon as symptoms occur.

Many cases of heat hives fade on their own in a few hours, but certain home remedies, prescription medications, and prevention techniques can ease symptoms and alleviate flare-ups.

Natural remedies

Home remedies you can try include aloe vera, which has known anti-itching properties, or a colloidal oatmeal bath, which can help reduce inflammation.

But prior to topical applications of this sort, remember to check the ingredients to ensure that you arent allergic to any of them.

You can also take a few precautions to help prevent heat hives:

• Try to keep cool while exercising.
• Prevent exposure to areas of high humidity.
• Avoid prolonged periods of direct sunlight exposure.

Medications

If such home remedies dont work, your doctor may recommend beginning taking an antihistamine such as:

• H1 antihistamines such as citirizine (Zyrtec, Aller-Tec, and Alleroff) or loratadine (Claritin)
• H2 antihistamines (H2 blockers or antagonists) such as famotidine (Pepcid, Pepcid AC) or cimetidine (Tagamet, Tagamet HB)

If these medications dont relieve the symptoms sufficiently, your doctor may prescribe other drugs to reduce outbreaks. These include:

In some cases, your doctor may prescribe a medication off-label. One example of such medication is dupilumab (Dupixent), which is another biologic medication that has shown promising results in the treatment of heat hives.

Most instances of heat hives can be treated at home and eventually fade on their own. However, you should seek immediate medical attention if swelling occurs in your throat that makes it difficult to breathe. This can be a sign of a serious allergic reaction and anaphylaxis.

You and your doctor can work to identify the specific triggers of your heat hives and develop a prevention plan with ways to ease symptoms if flare-ups do occur.

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What to do if antihistamines stop treating hives

Antihistamines are a common treatment option for hives, but they may not be effective for everyone. They may also stop working over time. Identifying hives triggers and avoiding them may help prevent flare-ups.

Hives are an allergic skin reaction that appears as raised patches, bumps, or a combination of both. They may also be itchy or inflamed. Healthcare professionals may refer to hives as urticaria.

Doctors treat hives with several different therapies, including antihistamines.

This article discusses why antihistamines may not work, hives triggers and how to identify them, other treatment options, how to manage hives at home, and when to speak with a healthcare professional.

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Doctors often prescribe antihistamines for hives. Antihistamines are a type of medication that blocks histamine, which is a substance the immune system releases when it detects a potential threat to the body. Histamine causes several effects in the body including inflammation, itchy skin, and flushing.

Researchers have suggested two possible reasons that antihistamines may not work: not taking medications as directed and insufficient dosing.

An older 2009 study noted that previous studies on antihistamines for chronic hives reported between 4490% effectiveness.

The study authors speculated that part of the reason antihistamines may not work could be that some people take them on an as-needed basis or when symptoms occur. They suggested that a person should take antihistamines every day for consistent results.

However, the exact dose and how often a person should take them depends on the medications half-life, which is the time it takes for the medications active substance in the body to reduce by half.

In a 2023 review of studies, researchers stated that second-generation antihistamines are not always effective at treating chronic spontaneous hives. Their findings indicated that people may need to take up to two times the standard antihistamine dose for better efficacy. However, they suggested that future studies into the safety and efficacy of increasing the dose are necessary.

Similarly, a 2017 study suggested that updosing antihistamines dosage fourfold may help reduce the need for a third line of therapy for chronic spontaneous urticaria by about 49% with a limited increase in reported side effects.

Trigger identification and management can play a role in helping a person find relief from chronic hives. Triggers are anything that causes hives to occur. They can vary between people.

Some possible causes and triggers of hives can include:

While many people can identify the underlying cause of their hives, experts estimate that millions of Americans develop hives during their lifetime with no known cause. Some of these individuals may develop chronic spontaneous urticaria, which healthcare professionals define as hives lasting for 6 or more weeks.

A person should consider writing down when they have a flare and include information such as what they were doing, eating, and so on. This may help the person narrow down or figure out what may be triggering their hives.

The table below shows approximate times from trigger exposure to hive development.

Antihistamines are one possible treatment for hives. Dermatologists and other doctors may prescribe or recommend a person take one or more other medications to help treat and prevent hives. These can include:

• corticosteroids
• anti-itch cream or lotion
• autoinjector (EpiPen)
• phototherapy, which involves a healthcare professional shining ultraviolet light on areas of the skin
• omalizumab (Xolair)

If antihistamines or any of the treatments above are not working, a doctor may recommend other medications, such as cyclosporine or hydroxychloroquine, which help calm the immune system.

In addition to treatment options a doctor may offer, a person can take steps to help manage their hives at home. Some self-care tips for hives include:

• applying a cold compress to the skin
• taking a colloidal oatmeal bath
• wearing 100% cotton, loose fitting clothes
• using gentle cleaners without fragrances
• keeping track of when hives occur
• avoiding scratching skin that itches
• taking lukewarm baths and showers

It is recommended that a person consider talking with a doctor if they develop hives that do not go away. A doctor can help develop a treatment plan and help a person figure out what may be causing the hives.

If treatments do not appear to help, it is important that a person discusses this with a healthcare professional who can make any necessary changes to their treatment plan such as adjusting medications.

It can be helpful for a person to consider keeping a journal of when their hives appear and bringing it along to their doctors appointment. It can be helpful for a person to record important information about the hives, such as when they occur, what type of food the person was eating, any other possible triggers, the severity of the hives, and how long they last.

Some research suggests that antihistamines for hives may not work if the dose is not high enough or a person does not take the medication daily or as a doctor prescribed.

Working out what is causing the hives may help direct treatment. A doctor can provide several different treatment options for a person, such as corticosteroids, phototherapy, and anti-itch creams.

If antihistamines or other treatments do not work, it is important that a person discusses this with a doctor so they can recommend other options.