Hives (urticaria) are red, itchy welts that result from a skin reaction. The welts vary in size and appear and fade repeatedly as the reaction runs its course.
The condition is considered chronic hives if the welts appear for more than six weeks and recur frequently over months or years. Often, the cause of chronic hives is not clear.
Chronic hives can be very uncomfortable and interfere with sleep and daily activities. For many people, antihistamines and anti-itch medications provide relief.
Signs and symptoms of chronic hives include:
- 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
Short-term (acute) hives appear suddenly and clear up within a few weeks.
The welts that come with hives arise when certain cells release histamine and other chemicals into your bloodstream.
Doctors often can’t identify the reason for chronic hives or why acute hives sometimes turn into a long-term problem. The skin reaction may be triggered by:
- Pain medications
- Insects or parasites
- Heat or cold
- Alcohol or food
- Pressure on the skin, as from a tight waistband
In some cases, chronic hives may be related to an underlying illness, such as a thyroid disease or, rarely, cancer.
Chronic hives don’t put you at any sudden risk of a serious allergic reaction (anaphylaxis). But if you do experience hives as part of a serious allergic reaction, seek emergency care. Signs and symptoms of anaphylaxis include dizziness, trouble breathing, and swelling of your lips, eyelids and tongue.
Your doctor will do a physical exam and ask you a number of questions to try to understand what might be causing your signs and symptoms. He or she may also ask you to keep a diary to keep track of:
- Your activities
- Any medications, herbal remedies or supplements you take
- What you eat and drink
- Where hives appear and how long it takes a welt to fade
- Whether your hives come with painful swelling
If your physical exam and medical history suggest your hives are caused by an underlying problem, your doctor may have you undergo testing, such as blood tests or skin tests.
Your doctor will likely recommend you treat your symptoms with home remedies, such as over-the-counter antihistamines. If self-care steps don’t help, talk with your doctor about finding the prescription medication or combination of drugs that works best for you. Usually, an effective treatment can be found.
Taking nondrowsy antihistamine pills daily helps block the symptom-producing release of histamine. They have few side effects. Examples include:
If the nondrowsy antihistamines don’t help you, your doctor may increase the dose or have you try the type that tends to make people drowsy and is taken at bedtime. Examples include hydroxyzine pamoate and doxepin .
Check with your doctor before taking any of these medications if you are pregnant or breast-feeding, have a chronic medical condition, or are taking other medications.
If antihistamines alone don’t relieve your symptoms, other drugs may help. For example:
- Histamine (H-2) blockers. These medications, also called H-2 receptor antagonists, are injected or taken orally. Examples include cimetidine , ranitidine and famotidine .
- Anti-inflammation medications. Oral corticosteroids, such as prednisone, can help lessen swelling, redness and itching. These are generally for short-term control of severe hives or angioedema because they can cause serious side effects if taken for a long time.
- Antidepressants. The tricyclic antidepressant doxepin , used in cream form, can help relieve itching. This drug may cause dizziness and drowsiness.
- Asthma drugs with antihistamines. Medications that interfere with the action of leukotriene modifiers may be helpful when used with antihistamines. Examples are montelukast and zafirlukast .
- Man-made (monoclonal) antibodies. The drug omalizumab is very effective against a type of difficult-to-treat chronic hives. It’s an injectable medicine that’s usually given once a month.
- Immune-suppressing drugs. Options include cyclosporine and tacrolimus .