Hives and not a clue.. Please help

Well, it started a little over a year ago, during the winter. I'd break out in hives that were long and skinny and they'd come and go, finally they just went and never came back. But during that summer i had went to the beach and when i was laying out in the sun i broke out on my back in these small red circles. After that they got worse, continuing to form all over my back and chest and are now working their way up my neck. I break out after a shower, when its hot, when im upset or anytime my body temp rises. They never really go away; they turn the color of my skin and are not as noticeable at times. The hives have now grouped together, pretty much as one big hive.
During the last year and a half ive been in a relationship and have become sexually active. Before the hives occured on my chest, when my bf and i would have sex, afterwards i would break out red and itchy on my chest, but it would only last about 15 minutes and the skin was just red, no spots or bumps anywhere.

I know what im experiencing now is hives, i just dont know why its being caused. Any insight and advice would be most appreciated.

Thank you,
Cait

[Bhupinder Kaur, MD]

Hello,
Hives (medically known as urticaria) are red, itchy, raised areas of skin that appear in varying shapes and sizes. They have a tendency to change size rapidly and to move around, disappearing in one place and reappearing in other places, often in a matter of hours.

They are of two types:acute and chronic(when hives persist for more than 6 weeks). The most likely triggers for acute urticaria are allergies to pets, horses, latex and foods, such as shellfish and nuts,bee or wasp stings,allergies to medicines,Viral infections, such as glandular fever and herpes, dental and sinus infections, fungal infections, blood transfusions and vaccines.

The cause of chronic urticaria is often more difficult to identify. Most cases are called chronic idiopathic urticaria, which means they're caused by the body's unexplainable development of antibodies to itself (auto-antibodies).Chronic urticaria is often accompanied by coexistent physical urticaria, triggered by environmental exposure to heat, cold, sunlight, vibration, pressure on the skin or even exercise.

So exact cause of hives is difficult to determine.But you can consult an allergist and get skin tests and blood tests like RAST done to check whether there are any allergies.

Hope it helps.Take care and pls do keep me posted on how you are doing or if you have any additional doubts.Kind regards.