Cold urticaria or also known like cold allergy

Definition
As strange as it sounds, it’s possible to have an allergy to cold temperatures. Doctors refer to this as cold urticaria (ur-tih-KAR-ee-uh). It’s also sometimes called cold allergy or cold hives. With cold urticaria, exposure to cold temperatures causes redness, itching, swelling and hives on your skin. As much as possible, people with cold urticaria should avoid exposure to cold air as well as cold water. For example, swimming in cold water is the most common cause of a severe, whole-body reaction — leading to fainting, shock and even death.
If you think you have cold urticaria, consult your doctor. Treatment for cold urticaria may include antihistamines taken before cold exposure.
Symptoms
Cold urticaria symptoms begin soon after the skin is exposed to a sudden drop in air temperature or to cold water. Although symptoms may begin during the cold exposure, symptoms of cold urticaria are often worse during rewarming of the exposed skin. The majority of cold urticaria reactions occur when skin is exposed to temperatures lower than 40 F (4.4 C), but some people can have reactions to warmer temperatures. Damp and windy conditions may make cold urticaria more likely.
Cold urticaria signs and symptoms may include:
• Reddish, itchy hives (wheals) on the area of skin that was exposed to cold. Wheals generally last for about half an hour.
• Swelling of hands when holding cold objects.
• Swelling of lips when eating cold foods.
• In rare cases, severe swelling of the tongue and throat that can block breathing (pharyngeal edema).
In some people, reactions affect the whole body. This is known as a systemic reaction. Signs and symptoms of a severe reaction include:
• Fainting
• Chills
• Fast heartbeat
• Swelling of limbs or trunk
Severe reactions
For people who have cold urticaria, exposure to cold can be dangerous. The worst reactions generally occur with full skin exposure, such as swimming in cold water. A massive release of histamine and other immune system chemicals causes a sudden drop in blood pressure that can lead to fainting, shock and, in rare cases, death. In the case of cold-water swimming, drowning can be caused by loss of consciousness.
The severity of cold urticaria symptoms vary widely. Some people have minor reactions to cold, while others have severe reactions. It’s also impossible to say whether it will get better over time. In some cases cold urticaria goes away on its own after several months. In other cases it lasts many years before it improves.
When to see a doctor
If you have skin reactions after cold exposure, see a doctor. Even if the reactions are mild, your doctor will want to rule out any underlying conditions that may be causing the problem.
Seek emergency care if you a severe reaction after sudden exposure to cold. Get help right away if you:
• Feel lightheaded
• Have difficulty breathing
• Feel your like your throat is swelling
Causes
The cause of cold urticaria isn’t clear. Certain people appear to have overly sensitive skin cells, either due to an inherited trait or caused by a virus or other illness. Exposure to cold triggers the release of histamine and other immune system chemicals into the skin that cause redness, itching and other symptoms.
Risk factors
Cold urticaria can occur in any age group, whether you’re female or male. You’re more likely to have cold urticaria if:
• You’re a child or young adult. A type of urticaria called primary acquired urticaria occurs in children and young adults. This is the most common type of urticaria, and it usually improves on its own within two to three years.
• You recently had a viral infection. Mycoplasma pneumonia and mononucleosis have been linked to cold urticaria.
• You have an underlying health condition. Known as secondary acquired urticaria, this less common type of cold urticaria can be caused by an underlying health problem, such as rheumatoid arthritis, hepatitis or cancer.
• You have certain inherited traits. Rarely, cold urticaria is associated with an inherited condition called familial cold autoinflammatory syndrome. This condition causes painful wheals and flu-like symptoms after exposure to cold.
Complications
The main possible complication of cold urticaria is a severe reaction that occurs after exposing large areas of skin to cold, such as swimming in cold water.
Preparing for your appointment
You’ll probably first visit your family doctor or a general practitioner. However, you may then be referred to a doctor who specializes in allergic disease (allergist-immunologist).
Because appointments can be brief, and there’s often a lot of ground to cover, it’s a good idea to be well prepared for your appointment. Here’s some information to help you get ready for your appointment, and what to expect from your doctor.
What you can do
• Write down any symptoms you’re experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
• Write down key personal information, including any major stresses or recent life changes.
• Make a list of all medications, vitamins and supplements you’re taking.
• Write down questions to ask your doctor.
Your time with your doctor is limited, so preparing a list of questions ahead of time will help you make the most of your time together. List your questions from most important to least important in case time runs out. For cold urticaria, some basic questions to ask your doctor include:
• What’s the most likely cause of my symptoms?
• Are there other possible causes for my symptoms?
• How long will these hives last?
• What kinds of tests do I need? Do these tests require any special preparation?
• What treatments are available, and which do you recommend?
• Do these treatments have any side effects?
• Is there a generic alternative to the medicine you’re prescribing me?
• I have other health problems; are the recommended treatments compatible?
• Are there any brochures or other printed material that I can take home with me?
In addition to the questions that you’ve prepared to ask your doctor, don’t hesitate to ask questions during your appointment at any time that you don’t understand something.
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:
• When did you first begin experiencing symptoms?
• Have you recently been ill?
• Do others in your family have similar symptoms?
• Have you taken any new medications recently?
• Have you tried any new foods?
• Have you traveled to a new place?
• Does anything seem to improve your symptoms?
• What, if anything, appears to worsen your symptoms?
What you can do in the meantime
If you’re experiencing mild hives, these tips may help relieve your symptoms:
• Avoid irritating affected areas.
• Minimize vigorous activity, which can release more irritants into your skin.
• Use over-the-counter antihistamines to help relieve the itching.
Tests and diagnosis
Cold urticaria can be diagnosed by placing an ice cube on exposed skin for several minutes. If you have cold urticaria, a raised, red bump (hive) will form after the ice cube is removed.
Most cases of urticaria occur in children and young adults, and don’t have an apparent underlying cause. This type of urticaria usually gets better on its own after a few weeks to months, but in some cases it can last for years.
In some cases, cold urticaria is caused by an underlying condition that affects the immune system. Some conditions that can cause cold urticaria include hepatitis, rheumatoid arthritis, certain cancers or an infection such as mononucleosis. If your doctor suspects you have an underlying condition, you may need blood tests or other tests.
Treatments and drugs
There is no cure for cold urticaria, but treatment can help. Treatment includes avoiding cold temperatures and exposure to sudden changes in temperature. Medications can help prevent and reduce symptoms
Medications used to treat cold urticaria include:
• Antihistamines. These medications block the symptom-producing release of histamine. Some of these medications are available over-the-counter, whereas others require a prescription. Examples include loratadine (Claritin), fexofenadine (Allegra), cetirizine (Zyrtec), levocetirizine (Xyzal) and desloratadine (Clarinex).
• Cyproheptadine. This medication is an antihistamine that also affects nerve impulses that lead to symptoms.
• Doxepin (Sinequan). Normally used to treat anxiety and depression, this medication can also reduce cold urticaria symptoms.
These medications won’t cure cold urticaria — they’ll only ease symptoms. If you have cold urticaria because of an underlying health problem, you may need medications or other treatment for that condition as well.
Prevention
There’s no way to avoid getting cold urticaria in the first place, but you can help prevent symptoms by taking medications as prescribed and avoiding cold temperatures, especially cold exposure to unprotected skin.

source:  http://www.mayoclinic.com/health/cold-urticaria/DS01160