woman itching her elbow

What Triggers Cause Hives?

Hives, medically known as urticaria, affect one in five people at some point in life. This skin condition causes itchy raised welts, which can be either red or skin-colored and vary in size. You’re probably wondering, what is the cause of these hives?

Hives are the result of a skin reaction and will come and go in relation to specific triggers. Urticaria often develops right after or up to two hours after contact with a trigger.

Hives are the result of histamine release and other substances from mast cells found in the skin. These cause characteristic swelling and itchiness in affected areas. This skin reaction is either allergic in nature or non-allergic. We classify hives as acute and chronic.

There is an endless list of triggers that cause hives. Some of these triggers include insect stings, stress, food, and infections.

Read on to learn more about these triggers and a few tips you could use to avoid them.

cause hives - woman's back with hives

What Causes Acute Urticaria?

Acute urticaria hives last for less than six weeks. The symptoms come and go only when exposed to a trigger.

Acute urticaria is often caused by exposure to a natural substance, drug, physical stimulus, or infection. We can identify the trigger in most cases. However, in other cases, it can be hard to detect because new allergies may develop.

There are many things that cause acute hives.

Allergic Reactions

Some plants, pet dander, and pollen commonly cause hives. When someone who is allergic to these allergens comes into contact with them, hives may occur.


Almost any type of food can cause hives. However, the most common foods include:

  • Peanuts
  • Nuts
  • Eggs
  • Shellfish
  • Cow’s Dairy
  • Berries

In some cases, it’s food additives that cause hives. People who break out in hives after eating certain foods may have a food allergy. Seek medical advice for appropriate testing and diagnosis.

Insect Stings and Bites

Another common cause of hives is bee and wasp stings. Mosquito bites may also cause them on the skin.


Over-the-counter drugs such as aspirin and ibuprofen may cause hives. Antibiotics like penicillin and sulfa drugs also cause the reaction in susceptible individuals. There’s also a link between blood transfusions and the development of hives.


Believe it or not, stress affects your body physically as well as mentally. Stress promotes the release of histamine, which then leads to hives developing.

Acute Infections

Acute infections also cause hives. Common infections include strep throat and urinary tract infections.

Viral infections like mononucleosis, hepatitis, and the common cold can cause hives too. These hives typically don’t last more than a few weeks.

Synthetic Chemicals

When someone is sensitive to synthetic chemicals, they may experience hive reactions. Latex is a common material associated with causing hives. Although, it can also cause life-threatening anaphylaxis too.

Certain chemicals found in shampoos, makeup, or cleaning products may also cause hives.


Exercise is a very healthy way to take care of our bodies, however, it can cause hives.

Why does exercise cause hives? There are a few theories explaining the reasons.

During a workout, the body releases many chemicals, including acetylcholine. This substance may irritate skin cells and create a rash similar to hives. Furthermore, increased body temperature and sweating could increase the risk of hive development.

Natural Elements

Some people react to natural elements that cause hives. These include direct sunlight, cold temperatures, and strong winds. This is not a true allergic reaction, but a sign that your skin is more sensitive than normal.

cause hives - woman lifting shirt to show hives on lower back

What Causes Chronic Urticaria?

We consider urticaria chronic when hives appear for more than six weeks and reoccur. This means they appear on a regular basis over months and years. These chronic hives may be uncomfortable and interfere with day-to-day activities and sleep.

Idiopathic chronic urticaria. Idiopathic means that the cause was not identified. Most cases of chronic hives are idiopathic, as the exact cause is unknown.

However, there are some specific causes of chronic urticaria too.

Autoimmune Diseases

Both autoimmune and other diseases may cause chronic hives. The second most common reason for chronic urticaria is autoimmune diseases. These include lupus and Sjögren syndrome. Thyroid diseases and sometimes cancer may also lead to chronic hives.

External Factors

Much like acute urticaria, external factors may cause chronic hives. These include:

  • Stress
  • Exposure to sunlight
  • Extreme temperatures
  • Certain foods
  • Alcohol
  • Infections
  • Medications
cause hives - woman writing in journal

Can You Prevent Hives?

The best way to prevent hives is to identify triggers and avoid exposure, as much as possible. Your doctor may order allergy tests to identify triggers like pollen, pet dander, and medications. They may also order a complete blood count (CBC), hormone levels, liver function, and other tests.

Allergic reactions often cause hives and in serious conditions, anaphylaxis can develop. Food, drugs, and latex are often the reason for reactions. Seek immediate treatment if you experience trouble breathing, swelling, or dizziness.

It also helps to keep a journal to identify your triggers for hives. If you notice hives appear, review your last few days and look for the cause. Did they develop after a meal, while staying home, or being outdoors? Have you changed a personal care product or detergent? Did you start a new medication? How are your stress levels lately? Asking yourself these questions can help you identify your triggers and avoid them.

If your hives reoccur, talk to your doctor. Antihistamines or itch medications can help manage hives if the underlying cause is unknown. In some serious cases, your doctor may prescribe oral corticosteroids.

Your email address will not be published. Required fields are marked *