Risk factors

A person may be at greater risk of developing both hives and angioedema if he or she has or had:

• hives or angioedema before
• other allergic reactions             
• a family history of hives or angioedema
• a family history of hereditary angioedema

Diagnosis of urticaria

A doctor should ask many questions in an attempt to find the possible cause because, in most cases, this can be very difficult. Since there are no specific tests for hives or the associated swelling of angioedema, testing will depend on your medical history and a thorough examination by your dermatologist. Skin tests may be performed to determine the substance that you are allergic to.  
There are several lab studies that could confirm the diagnosis and the most common are:

• Stool examination for fecal ova, and parasites
• Antinuclear antibody titer
• Hepatitis B and C screen
• Thyroid function tests
• Tests for CBC (complete blood count), prostate-specific antigens, and serum calcium

Treatment of urticaria and angioedema

The standard treatment for hives and angioedema is antihistamines, which block the symptom-producing release of histamine, the chemical that leads to a swollen skin rash.

Antihistamines

Oral antihistamines control itching for the majority of patients with urticaria, but the problem is that they do not affect the underlying cause of the rash. Antihistamines may need to be taken intermittently or continuously until the underlying tendency toward urticaria disappears. Some of the most commonly used non-sedating antihistamines are:

• loratidine
• fexofenadine
• terfenadine
• cetirazine, and
• astemizole

Patients should also keep in mind that these antihistamines may be unsuitable during pregnancy. Terfenadine and astemizole may increase the risk of abnormal heart rhythms. 

Corticosteroids

For severe hives or serious types of angioedema, doctors may prescribe an oral corticosteroid drug, most commonly prednisone, which can help reduce swelling, redness and itching. These steroid medications stabilize mast cell membranes and inhibit further histamine release. They also reduce the inflammatory effect of histamine and other mediators, and can provide symptom relief quickly.

Other medications

It is very important to remember that these medications are often ineffective in treating hereditary angioedema. Medications used specifically to treat the hereditary form of this condition on a long-term basis include certain androgens, such as danazol (Danocrine®), that help regulate levels of blood proteins. Sometimes, only an urgent medical intervention can save the life of the patient because, in cases of a severe and serious attack of hives or angioedema, a patient may need an emergency injection of adrenaline and a trip to the emergency room to allow them to clear their airways.

Other medications include:

• Ultraviolet radiation treatment
• Antibiotics and antifungal agents, used to clear an assumed underlying infection or for non-specific anti-inflammatory action.
• Immunosuppressive medications
• Antifibrinolytic agents
• Tricyclic medications such as amitriptyline, nortriptyline and doxepin

Self care for hives and angioedema

Here are some of the most useful tips for the future self care, should you ever find yourself suffering from an episode of hives:

• Avoid irritating affected areas.
• Take cool showers.
• Reduce your intake of acidic fruits.
• Apply cool compresses.
• Wear loose, light clothing.
• Avoid alcohol (it causes the surface blood vessels to dilate).
• Minimize vigorous activity, which can release more irritants into the skin.
• Use over-the-counter antihistamines to help relieve the itching
• Cool the affected area with a fan, cold flannel, ice pack or soothing lotion.