If you’ve noticed a red, raised, itchy rash on your skin, you may have hives.
Hives are round or ring-shaped patches (weals) that form on your skin and they can appear anywhere on your body.
The condition can be triggered by an allergic reaction to food, infections, chronic health conditions, certain medications, stress or drinking alcohol -- and a variety of physical stimuli, including temperature changes or physical pressure.
But hives can also be triggered by factors usually associated with summer, or hot weather, such as insect bites, pollen, sun exposure and heat. It’s common for the condition to flare up in summertime.
If you have hives, you might be wondering how long it will take for your rash to fade. Most cases resolve within a day or 2, but the exact length of time will depend on the type of hives you have.
What are the different types of hives -- and how long do they last?
Acute hives (sometimes called acute urticaria or acute spontaneous urticaria) are hives that appear suddenly, and then fade away on their own.
They normally fade within 24-48 hours, although some cases of acute hives can last for several weeks.
You may notice that individual weals seem to fade after an hour or less, but new ones may appear in other places - giving you the impression that the rash is moving around your body.
Some people also experience swelling in the deeper layers of the skin (angioedema), which can affect any part of the body, but it often occurs on your hands, lips, feet, eyes or genitals.
Studies show that 1 in 6 people experience an episode of acute hives at some point in their lives. It’s often difficult to identify the cause of an outbreak, but the condition is normally harmless and you may be able to manage some of your symptoms at home.
Chronic or persistent hives are hives that last for more than 6 weeks, but they normally last between 6 and 12 months, sometimes longer, according to the British Association of Dermatologists.
If you have chronic hives, you may find that your symptoms either come and go intermittently, or you have an itchy, red rash on most days.
Chronic hives can be the result of an autoimmune condition like rheumatoid arthritis or lupus. Research also shows that chronic hives can be linked to illnesses like viral hepatitis and an underactive thyroid (hypothyroidism), but for some cases of chronic hives there isn’t an obvious cause or trigger.
If you think that you might have chronic hives, you should see a doctor to help identify any possible triggers and causes. A doctor may also be able to prescribe medications to help you control your symptoms.
Physical urticaria is the medical name for any type of hives that are triggered by a distinct, physical stimulus. For example, some people break out in hives when they sweat, or rub their skin.
Other people find that cold temperatures, sunlight or friction trigger an outbreak, and in some rare cases, water can also be a trigger for hives.
If you have physical urticaria, your hives will normally develop within minutes, and then fade within 1 hour. If you think that you may have this form of hives, try to identify your triggers and avoid them as much as you can.
You may also find that it helps to take an antihistamine when you break out in a rash, but you should see a doctor if you intend to take antihistamine medications for more than a couple of days in a row.
When to see a doctor about hives
You should see a doctor if your symptoms do not improve after 2 days, your rash seems to be getting worse or your hives keep going away and then coming back, as this could be a sign that you are allergic to something.
You should also see a doctor if you have a high temperature or notice any swelling under your skin (angioedema).
You should seek medical attention immediately if you have any of the following symptoms:
- difficulty breathing
- difficulty swallowing
- dizziness or fainting
- nausea or vomiting
- an increased heart rate
- rapid and severe swelling of the face, mouth or throat