What happens if hives don t go away with Benadryl

By Isabella Storyclaire

last updated January 15, 2025

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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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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 Treatment CenterOver 150,000 patients helped since 2001

Benadryl and many of the other OTC antihistamines claim to be effective for treating hives, but for most people suffering from urticaria, the reality is that it barely helps at all. So what do you do if you're one of the 64% of the populace for which Benadryl doesn't work?

How Booked Out Is Your Dermatologist?Most people will immediately turn to their dermatologist, but like me, almost every dermatologist I know is booked out weeks to months in advance. And waiting that long to just get evaluated (let alone treated) is not a viable solution for the majority of people. When you're experiencing a terribly itchy rash, the last thing you want to hear is "We have an opening 3 weeks from now."

New OTC Medication That's Better Than Benadryl

Because hives won't go away with just Benadryl and because it can take almost a month to get an appointment with your dermatologist, I recommend my patients have OxyHives on hand for when they have a hives outbreak. Unlike Benadryl, OxyHives is specifically designed to JUST make hives go away. It's non-addictive, and unlike antihistamines, it won't make you drowsy. Simply put two sprays under your tongue and the hives go away naturally within 1-2 hours. OxyHives is available online at http://www.oxyhives.com

How To Get Rid Of Hives When Benadryl Won't Work

While OxyHives is the only OTC rememdy scientifically formulated to make your hives outbreak go away fast, there are other home remedies that can help at least lessen the itchy, burning feeling that your hives are causing.

#1. Take a Cool Bath - NEVER TAKE A HOT BATH OR SHOWER

Because hot water (and usually even warm water) can make your outbreak worse, you should always take cool baths. Feel free to add some uncooked oatmeal (rolled oats), baking soda or colloidal oatmeal, which will usually helps relieve the itchy feeling by blocking any further release of histamine. Like Benadryl, a cool bath won't make your hives go away, but at least it'll calm your angry skin.

#2. Apply a Cool, Wet Compress

If you don't happen to have a bath tub, you can also get temporary relief from your itchy rash by applying a cool, wet compress to the welts. This will help soothe the irritation and should help deter you from scratching the affected area.

#3. Apply Some Calamine Lotion or Witch Hazel Witch hazel and calamine lotion may not smeel very good, but because they are anti-stringents, they can be effective at helping to shrink the blood vessels near your welts so that they don't leak as much histamine. Witch hazel and calamine lotion won't make your hives rash go away, but they are a good bandaid until your OxyHives arrives.

#4. Avoid All Scratchy ClothesBecause your skin is hyper-sensative right now, you MUST avoid all scratchy clothing. Instead, put on your loosest fitting, most comfortable clothes that are smooth to the touch. Fabrics like wool will drive you bonkers, so avoid these itchy fabrics at all costs.

#5. Other At Home Remedies To Try Until You Have OxyHivesWhile the following home rememdies won't make your hives go away like OxyHives will, they should provide you with some temporary relief from the itchy feeling you currently have. Because of theiralkaline nature, Pepto Bismol or Milk of Magnesia should temporarily help relieve the itching a little. You can also try applying asmall amount of baking soda and water mixed together into a paste, which some of my patients have told me helps a little. Cream of tarter is good alternative if you don't have baking soda on hand. I have also been told that 1 tablespoon of vinegar (any kind will do) mixed with 2 tablespoons of cool water is another good alternative.

Benadryl AlternativesWhile all of the above home remdies will help reduce the itchy feeling you currently are experiencing, the only OTC (over the counter) medication that is scientifically formulated to make your hives go away is OxyHives. If you don't already have OxyHives on hand, you can order it at http://www.oxyhives.com