Why am I getting hives all of a sudden

By Isabella Storyclaire

last updated September 16, 2024

Contributions sourced from

Hives: Causes

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7 Reasons Why You Might Be Breaking Out in Hives

Hives are confusing AF: The oddly-shaped reddish spots can disappear and reappear faster than an ex-BF. As it turns out, these transient little buggers are actually quite commonthey affect about 20 percent of people at some point, says Whitney Bowe, M.D., a New York-based dermatologist. So, theres a decent chance you may experience hives in your lifetime (yay!).

Although the cause is sometimes obvious (if you're allergic to peanuts and you accidentally eat one, the welts may appear almost immediately), oftentimes it can be difficult to figure out why, exactly, you have hives. The good news is that, for the most part, they don't last more than 24 hours and are easily treated with antihistamines, according to the American College of Allergy, Asthma, and Immunology.

Here are a few reasons why you might find yourself covered in splotches:

1. You Take Certain MedicationsNon-steroidal anti-inflammatories (like aspirin and and ibuprofen), opioids (like morphine and oxycodone), and antibiotics (like penicillin), can all make you break out in hives, says Bruce Brod, M.D., clinical professor of dermatology at the Perleman School of Medicine at the University of Pennsylvania. According to the American Academy of Allergy, Asthma, and Immunology, hives will usually develop within an hour of popping the pill.

2. Youre StressedAnother reason to take a deep breath: Intense emotions can prompt hives. That's because stress causes your immune system to falter, making you more susceptible to skin issues. Typically, stresshivesare short-lived (i.e. they last less than a day) though, says Brod.

3. You Got Really SweatyAccording to the World Allergy Organization, heat-induced hives (which can be caused by exercise, hot showers, sweating, and anxiety), generally start on the neck and upper chest and spread to the face, back, and extremities. If this happens to you regularly, Bowe suggests consulting your doc, who can put you on an antihistamine regimen.

4. You Came Into Contact with an Allergen in the EnvironmentSummertime and the livin is itchy. Environmental factors that can spark an outbreak include sunlight, heat, cold, grass, pollen, and dust mites, says Lauren Ploch, M.D., a dermatologist in Augusta, Georgia.

5. Youre Wearing Too-Tight ClothesSome people will develop hives in areas where there is more pressure on the skin, such as on the bottom of their feet and underneath tightly-fitting clothing or underwear, says Brod. He recommends resisting the urge to scratchand wearing loose-fitting clothing. (Leave those skinny jeans at home!)

6. You Have an Autoimmune DiseaseIf you still have hives after an extended period of time (a month or more), an autoimmune disease may be to blame. Lupus or thyroid disease can cause hives, says Ploch, who adds that type 1 diabetes, Sjogren's syndrome, and celiac disease could also be to blame. Attributing hives to an autoimmune disease is often a process of elimination, though, she says, so its important to check in with your doctor.

7. You Ateor DrankSomething FunkyWe know its a total buzz kill, but alcohol and some foods can cause hives. We see a lot of allergic reactions from food and food additives, which is where things can get confusing because its not necessarily the food itself, says Ploch. Common culprits include shellfish, eggs, and nuts, while Ploch notes that azo food dyes in candy (red, yellow, and orange colors) and the sulfites in wine and deli meat can cause hives, too. If hives are issue for you, its important to take a careful history of what you eat so that you can avoid those triggers in the future, says Ploch.

Hives and angioedema

Overview

Hives

Illustration of hives on different skin colors. Hives can cause swollen, itchy welts. Hives is also called urticaria.

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