Urticaria are a red, raised, itchy skin rash that is sometimes triggered by an allergen. An allergen is something that produces an allergic reaction. It is also known as hives, welts, weals, or nettle rash. It affects around 20 percent of people at some time in their life. It is not contagious.

Batches of red or skin-colored welts (wheals), which can appear anywhere on the body; Welts that vary in size, change shape, and appear and fade repeatedly as the reaction runs its course; Itching, which may be severe; Painful swelling (angioedema) of the lips, eyelids and inside the throat; A tendency for signs and symptoms to flare with triggers such as heat, exercise and stress; A tendency for signs and symptoms to persist for more than six weeks and to recur frequently and unpredictably, sometimes for months or years; are the different symptoms of urticaria or hives.  Short-term (acute) hives appear suddenly and clear up within a few weeks.

The exact cause of urticaria is not known. But there are some trigger factors that can cause urticaria are:- Pain medications; Insects or parasites; Infection; Scratching; Heat or cold; Stress; Sunlight; Exercise; Alcohol or food; Pressure on the skin, as from a tight waistband etc. In some cases, chronic urticaria may be related to an underlying illness, such as a thyroid disease or, rarely, cancer.

Urticaria, can be acute or chronic:-

Acute urticaria is the most common type. Symptoms last less than 6 weeks, and they typically affect the face and neck, fingers, toes, and the genitals of males. However, any part of the body can be affected.

Chronic urticaria continues for more than 6 weeks. About 1 in every 1,000 people is estimated to experience chronic urticaria.

Angioedema may also occur. This is similar to hives, but it affects the deeper layers of the skin.

The acute urticaria can be diagnosed by properly examining the skin rashes and a proper history taking. And in the case of chronic urticaria the trigger is probably not external, so experts do not recommend allergy tests at this point.

The following tests can check for underlying health conditions:-

blood test to check for anemia; stool sample to identify any parasites; erythrocyte sedimentation rate (ESR) test, to identify problems with the immune system; thyroid function test to assess for an overactive thyroid, known as hyperthyroidism, or hypothyroidism, an underactive thyroid; liver function tests, in case there are liver problems. 

Apart from allopathic treatment you can also opt alternative method of treatment like Ayurveda where various therapies and medicines are prescribed. The various therapies are Vamana, Virechana etc. Some of the ayurvedic medicines are Aarogyavardhini vati, Haridrakhand, patolakaturohinyadi kashayam, Khadirarishta, Nimb churna, Eladi oil.  Herbs like haridra , nimaba , amrita,Katuki, Nishotha, triphala helps in the condition.

 DIET RECOMMENDATIONS (AAHAR):-

Avoid milk and milk products, fish and other sea foods which likely cause allergy; Use ushnodaka (Warm water) for drinking; Consume kapha-suppressing foods and herbs such as lighter fruits (apples and pears), honey, beans, grains, spices and vegetables; Avoid salt, heavy fruits (oranges, bananas, pineapples, figs, dates, avocados, coconuts and melons), tofu, nuts, and certain vegetables (tomatoes, cucumbers, and sweet potatoes)

LIFESTYLE CHANGES (VIHAR)

Avoid contact with cold objects, artificial cooling devices and exposure to cold winds; Avoid certain food / medications which aggravates  the symptoms; Avoiding factors such as excess intake of salt, sour gruels and mustard; exposure to cold wind; improper emesis; insect bite; Oil massage over the body with Eladi Taila; Apply Aloe Vera gel when rashes appear; Neem paste also can be applied externally. 

See a doctor if the outbreak doesn’t disappear in a few days. And get medical help right away if you notice symptoms of angioedema (such as swelling of the lips, tongue, or throat) or a severe allergic reaction (anaphylaxis).