When its damp or cold out, do you suffer from itchy red hives? Marcie Fraser reports on urticaria, a condition that reacts to the cold.

Hives, or the medical term urticaria, is a common allergic reaction on the skin that affects nearly 25 percent of the population.

It is a physical allergy and is caused by cold air or cold water, which causes itchy, red welts or raised hives. In most cases the hives go away within a few hours, but for some sufferers, it can be weeks.

Dr. Teresa Copeland explained, "There are different types of cold induced urticaria. Some patients it is so severe, if they hold a cold Coke can, their hand becomes swollen and itchy. Other patients can't jump into lake water or pond because they'll break out in hives or have an asthma attack with that."

Shopping in an air conditioned market can bring on urticaria. Most often it is just annoying, but for some people, it can be dangerous. The reactions can be anaphylactic, which are similar to a bee sting or peanut allergy.

"The danger for someone who has a really more severe reaction is say they jumped into a cold pond and they had the swelling and their blood pressure might drop, in addition to the hives and itching. That's dangerous so for those people, they should never swim or exercise without a buddy and they should probably have an injectable adrenaline," said Dr. Copeland.

There is no predisposing factor for urticaria but it can be linked to an underlying auto-immune disorder including lupus, or thyroid disease or rheumatoid arthritis. Aside from avoiding exposure to cold, medications can be helpful.

"Antihistamines or sometimes H2 blockers like Tagamet or Zantac. We try not to use Prednisone unless we have to, because there are many side effects and Prednisone is not good to use on a chronic basis for months and months at a time," said Dr. Copeland.

Urticaria and other allergies can sometimes be affected by age, some people outgrow them and surprisingly for women, hormones can play a role.

Dr. Copeland said, "Some women, when they start having their periods, sometimes that is a trigger for their allergies and asthma. When they have had a pregnancy, sometimes that can change things for them too. Menopause is another time. I think hormones, at least for women, do play a role."