Why won t my hives go away with antihistamines

What to Do When Antihistamines Arent Working for Hives

Antihistamines may not work for some people, depending on the severity of their hives. You may need an increased dosage or a different medication altogether.

After a chronic idiopathic urticaria (CIU) diagnosis, your doctor will likely prescribe an oral antihistamine to treat your symptoms. However, antihistamines arent always effective.

If youve already tried an antihistamine and you arent seeing results, schedule an appointment with your doctor to learn about possible next steps.

Here are some questions you can ask your doctor at your follow-up appointment and some information about what you might hear in response.

Its hard to say why antihistamines work for some people and not for others. But its not uncommon for antihistamines to be or become ineffective.

Research on the effectiveness of antihistamines for chronic hives has shown a response rate as low as 43%. It took a secondary treatment with additional medications to bring 28% of the subjects into remission.

Antihistamines may stop working because hives can become worse over time or because the intensity of hives can wax and wane over time.

Its also possible that antihistamines become less effective because people arent taking them as prescribed.

Even if you cant identify the cause of your CIU, you may be able to pinpoint triggers that bring on outbreaks or increase the severity of your hives.

See whether any of the following common triggers seem to affect you:

• pets or pet dander
• exposure to extreme heat or cold
• exposure to direct sunlight
• vigorous exercise
• pressure on the skin
• stress or anxiety
• nonsteroidal anti-inflammatory drugs (like ibuprofen)

By understanding your personal triggers, you can put yourself in a better position to avoid them.

After seeing little to no results from an antihistamine, your doctor may suggest that you try the following treatments, usually in the following order:

• Higher dose: Sometimes increasing the dose of your current antihistamine can yield better results.
• A different antihistamine or a combination of several different antihistamines. Your doctor may consider switching you to a different antihistamine or putting you on a regimen of two types of antihistamines. For example, they may recommend an H1-antihistamine combined with an H2-antihistamine, which targets different receptors in the body.
• Oral corticosteroids. While doctors usually dont recommend prolonged use of steroids due to potential side effects, they may recommend a short course. This is especially likely if your hives are severe or if theyre accompanied by swelling.
• Cyclosporine (Gengraf, Neoral, Sandimmune): This is an immunosuppressant drug that has led to remission from hives in 50% of cases, according to research.
• Omalizumab (Xolair). Your doctor may recommend omalizumab, a medication thats injected once a month if your hives are difficult to treat, but is effective in 80% of cases.
• Leukotriene receptor antagonists (LTRAs): Two drugs, zafirlukast (Accolate) and montelukast, might be prescribed in cases of hives caused by Aspirin, and there isnt enough data on their effectiveness on hives overall.

If your medication isnt giving you the relief you need, you can try the following methods to ease itching:

• Moisturize regularly with lotion.
• Use cool water when you shower.
• Apply a cold compress or an ice pack to affected areas.
• Try using over-the-counter creams such as calamine lotion.
• Wear loose clothing made from 100% cotton or 100% silk.

While none of the above methods will treat your CIU, they can at least provide comfort during a flare-up.

Dietary changes to help prevent hives

Researchers are still studying whether changing your diet can impact the severity and duration of CIU flare-ups.

A 2018 preliminary Korean study suggests that an antihistamine diet, where you avoid foods that contain high levels of histamine, may help reduce the severity on an individual level.

Since this and other similar studies only involved a small group of participants, researchers arent ready to draw wide conclusions about the diets success rate.

Even so, it may be worth talking with your doctor to see whether changing your diet is a good option.

No. Hives are never contagious, so you dont need to worry about spreading them to friends, family members, or others who are in close contact.

You also dont have to worry about the hives spreading if you touch other parts of your body after touching your hives.

If youre concerned about what other people will think when they see the welts on your skin, you can ask your doctor to provide a note explaining the nature of CIU and its symptoms. This can be especially useful for school-aged children.

No. While it may be frustrating to learn that antihistamines arent effective at treating your hives, you dont need to worry that they will leave any permanent marks or scars.

Most hives last for no longer than 24 hours and should fade and disappear after that.

While most cases of CIU arent dangerous, there are several warning signs that you should be aware of. Sudden and severe hives can mean youre experiencing an allergic reaction and need urgent medical attention.

If you experience any of the symptoms of anaphylaxis alongside a hives outbreak, call 911 or go to the emergency room:

By definition, chronic means that your hives will last for 6 weeks or more. But theres no way to say for sure exactly how long a specific outbreak episode will last. It could be months or even years.

Each individual welt will probably last for several hours, but theyre often quickly replaced by new ones.

The good news is that CIU can go away, its just hard to predict when.

Should I see an allergist?

If youve already been diagnosed with CIU, your doctor believes the cause is unknown and an allergy isnt to blame. But if you suspect that your doctor overlooked an underlying allergy, you may want to consider seeing an allergist.

What happens if hives dont go away with Benadryl?

Benadryl (diphenhydramine) is an over-the-counter antihistamine that can be used to treat mild allergic reactions, including hives. It is an H1 antihistamine, which means it is one of the ones your doctor may want you to try first. It is also available in higher doses as a prescription if the OTC version doesnt work for you. If its still ineffective, your doctor will likely switch you to H2 antihistamines, other medications, or a combination of drugs.

Why is Benadryl not stopping my allergic reaction?

If there is an ongoing trigger for your hives in your environment, you might continue to develop them or they may worsen even if youre taking an antihistamine like Benadryl. In addition to taking medication, its important to try to identify the trigger and eliminate it. To do this, make an appointment with a dermatologist or allergist for testing, and track your flare-ups. That said, sometimes there is no identifiable cause. Make sure you are taking your medication exactly as prescribed or following the directions on the box of any OTC drug.

If antihistamines dont work for you, dont become discouraged. This happens for certain people and under certain circumstances.

Ask your doctor about possible next steps. Whether that involves a different form of medication or introducing some natural steps to reduce itching, you have options to decrease CIU-related discomfort.

Why won't my hives go away?

Q.I've gotten hives from time to time when I've been overly stressed. But now I have a case that won't quit after six weeks. What's going on?

A. No one welcomes these red, itchy welts that crop up on our skin. Many things can lead to a temporary case of hives, including allergic reactions to food, medications, bug bites, pollen, latex, or animal dander. Like you, some people also develop them when they're stressed, or in response to ultraviolet light or excess skin pressure. Hives are more common in women than men, especially from our 30s to 50s.

Most cases of hives go away within several days to a couple of weeks. If they last six weeks or longer, you may have autoimmune hives. This happens when your immune system mistakenly targets healthy tissue in this case, triggering a skin reaction. Autoimmune hives are more common in people with other autoimmune conditions, such as lupus, thyroid disease, rheumatoid arthritis, or celiac disease. Anyone whose hives last longer than a few weeks should see a doctor.

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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.