Top 10 Triggers for Hives

by Kristina Brooks Editor

Hives can come in different forms--acute, chronic or physical--and have an even greater number of triggers. Here's a guide to the most common hive-causing triggers.


Hives from food are typically allergic, and can arise if you have a newly developed allergy, or from eating something you never knew you were allergic to. Up to 90 percent of reactions from food are caused by shellfish, nuts, eggs and milk. Allergic reactions trigger the release of histamines, which aside from hives, cause sweating, itching, and swelling.


Sometimes our body can develop new conditions based on a medicine we are taking. Hives is one of those conditions. Medicines that often cause hives include certain aspirin, or other NSAIDS such as ibuprofen, as well as high blood pressure medication and even strong prescription-grade painkillers, such as codeine. Typically, this will cause acute or non-lasting urticaria, but you should notify your doctor if it persists.

Insect stings or bites

Most times our skin becomes itchy red or swollen to a bug bite or sting, as a natural response to protect the body from foreign proteins in the insect's saliva. However, mosquito bites, bee stings or other bites may trigger a more serious allergic reaction, or anaphylaxis, causing hives to surface around the bite area. If you suspect you have more sensitive reactions, keep antihistamines nearby and if bitten, try a cool bath to relieve pain and swelling.

Physical stimuli

Some people who suffer from hives may find physical stimuli such as temperature or pressure on the skin are the cause. Pressure urticaria typically affects the legs, hands feet and buttocks from standing or walking too long, or wearing tight clothing. Cold urticaria, results from the body adjusting after being exposed to cold from weather, a/c or a cold pool. Heat urticaria is triggered by body heat from sweating, exercising or external heat.


Latex can cause a few types of reactions ranging in severity. Milder reactions (contact dermatitis or allergic contact dermatitis), are usually caused by detergent, manufacturing chemicals or disinfectants in the latex. These delayed reactions usually trigger red, dry or irritated areas. However, hives are caused by a more serious allergy or sensitivity to a protein found in latex, and trigger a more severe and lasting response.

Blood transfusions

Hives as part of an immune system response may present itself during or within 24 hours of a blood transfusion procedure. Other symptoms may also include fever, chills or itching. These reactions are known to resolve themselves on their own without any excess treatment. However, since these procedures are usually done under medical care, any reactions can be tended to by a medical professional.


Viral infections can account for more than 80 percent of all causes of acute hives in children. Some examples of viral infections are the common cold, mononucleosis, and hepatitis. Hives may also be caused by bacterial infections, including urinary tract infections and strep throat. The hives usually form as the infection begins to clear itself from the body, about a week or so after the illness arises.

Pet dander

Hives and even angioedema are usually caused as a result of a histamine reaction from an allergic reaction. An allergy to animals or pet dander may trigger the release of histamines within the body, which among other reactions, can cause hives to form.


Airborne allergies, such as an allergy to pollen, usually don't cause hives to form on their own. Hives usually surface as a part of a hay fever attack after an allergen is inhaled. Other airborne allergens include dirt or grass.


Chemicals in plants, such as histamines, acetylcholine or urushiol can cause irritating reactions following contact to the skin, including hives. These chemicals are often found in plants that are spiny or pierce the skin. Other leafy plants, such as poison ivy or poison oak that contains urushiol, trigger a host of unpleasant reactions.

Kristina Brooks
Meet Our Writer
Kristina Brooks

Kristina Brooks was a digital editor at HealthCentral with a background in animal biology, ecology, and health science. While studying broadcast journalism, she discovered the great need for health reporters that could translate research to the public. In her work, she hopes to use research to help consumers make smart decisions about their healthcare, and empower patients to stay confident and in charge of their chronic conditions. She helped launch HealthCentral's inaugural MythWeek.