How to Determine What’s Causing an Outbreak of Hives

It can be distressing to experience an outbreak of hives, especially when you don’t know the cause. Hives or urticaria, as it’s called in the medical world, affects up to one in ten people at some point in their lives. Most cases of hives are due to an allergic reaction, although this isn’t always the case. Sometimes viruses, autoimmune diseases, and even environmental factors such as exposure to heat or cold can cause an outbreak of hives. If you’re unfortunate enough to experience this common condition, how do you find out what’s causing it?

What Causes an Outbreak of Hives?

Hives or urticaria occurs when a trigger of some type causes release of a protein called histamine from cells in the blood stream known as mast cells. Histamine causes an inflammatory reaction which leads to large red blotches on the skin known as wheals to appear which can be quite itchy. Blood vessels also become leaky which causes swelling to occur. Although uncomfortable, an outbreak of hives can disappear as quickly as it appeared, although sometimes it will move around affecting different areas of the body. In rare cases, more serious symptoms can occur such as difficulty breathing or even shock.

How Do You Determine the Exact Cause?

The best way to determine the cause of an outbreak of hives is to keep an “allergy diary”. The objective is to write down everything you eat and drink along with medications you’ve taken as well as products and fabrics you’ve put on your skin. In most cases, if hives are allergic in nature, it’ll be something you were exposed to in the past twelve hours. Because foods are a common cause, particularly shellfish, nuts, and soy products; it’s important to document any foods you’ve tried and restaurants you’ve eaten in. Write down everything applied to the skin as well as medications and supplements taken. If you’ve worn new clothing or washed your clothes in a new detergent, note that too. Keep in mind that extremes in temperature and direct sunlight can trigger hives in some people. Insect stings and bug bites can also bring on a case of hives in sensitive individuals.

It may take several outbreaks of hives to pinpoint the cause, so be prepared to play detective for awhile. By keeping a regular allergy diary, you may be able to pinpoint the exact cause. It’s important to let your doctor know if you develop an outbreak of hives since, in very rare cases, life threatening symptoms can occur. It’s also a good idea to keep antihistamines on hand to treat the itching and swelling.

The Bottom Line?

If an outbreak of hives becomes a chronic problem or the symptoms won’t go away, make an appointment for a thorough health evaluation to rule out underlying viruses or an autoimmune condition that could be causing the immune system to overreact. In some cases, allergy testing may be needed.