Hives are raised, red welts on the surface of your skin that are often itchy. They are normally the result of an allergic reaction to an irritant such as food or medications. In many cases, hives are harmless, go away on their own and do not leave any lasting marks. However, hives can be more serious, require antihistamine medications and even be life-threatening.
Causes of Hives
When you experience an allergic reaction to any substance, your body releases histamine as well as other chemicals into your blood stream. As a result, you experience itching, swelling and other symptoms. Swelling usually occurs around the face, lips and eyes. This is known as angioedema. Angioedema can also affect the hands, throat and feet.
Substances that may cause hives include:
- Insect bites
- Animal dander (in particular cat dander)
- Foods (especially shellfish, nuts, eggs, milk and fish)
Less common causes of hives:
- Emotional stress
- Excessive sweating
- Infections (such as mononucleosis)
- Extreme cold or sun exposure
- Illnesses (including leukemia, lupus and other autoimmune disorders)
Risk Factors for Developing Hives:
Hives and angioedema are a common condition that can and may affect virtually anyone at some point in time or another. You may be at an increased risk if you fall into one of the following categories:
- Previous hives or angioedema
- Have allergies or have had a previous allergic reaction
- Have an immune disorder associated with angioedema, such as lupus, lymphoma, leukemia or thyroid disease.
- A family history or hives or angioedema.
Signs and Symptoms of Hives
There are number of different signs and symptoms you may experience should you develop hives. These symptoms may include one or more of the following:
- Raised red or white welts on your skin. These welts may vary in size and will often cover large areas of your skin.
- Welts that resolve themselves as new welts are developing on your skin. The welts may also move from one area of your skin to another.
- Itching. The itching you experience may range from mild to severe.
- Occasionally (while rare), you may experience burning and stinging.
Complications Associated with Hives
While rare, some individuals may experience complications as a result of hives. Complications can include:
- Itching and discomfort (the most common complication of hives)
- Loss of consciousness
- Breathing trouble
- Anaphylactic shock, which is a severe allergic reaction that affects your heart as well as your lungs. When you go into anaphylactic shock, your bronchial tubes become narrower. As it result, it becomes very difficult to breath and your blood pressure drops. This may result in dizziness, loss of consciousness and in some cases death.
Angioedema is a reaction that is very similar to hives. This condition affects the deep layers of your skin as well as the lining of your intestines and throat. Angioedema will often appear around your cheeks, eyes and lips. You may also notice angioedema on your hands, feet or genitals. This can also affect your bowels as well as the insides of your throat. Angioedema can occur on its own or with hives.
Signs of angioedema can include:
- Swelling of your skin
- Warmth in the affected region of your skin
- Large, thick and firm welts.
- In severe cases, trouble breathing and swallowing.
There is also another form of angioedema known as hereditary angioedema. This condition is genetic and more serious. It can cause sudden, severe and very rapid swelling of your arms, face, legs, feet, hands, airways, genitalia and your digestive tract.
Indicators of hereditary angioedema can include:
- Sudden and/or severe swelling of your arms, hands, legs, feet, face, digestive tract airways and/or genitalia.
- Abdominal cramping, which is often the result of swelling that occurs in your digestive tract.
- Breathing and swallowing difficulties that occur as the result of swelling that obstructs your airways.
Treatment of Angioedema:
Mild symptoms of angioedema may not need treatment and will often resolve themselves. Moderate to severe symptoms may require medical treatment. If you experience breathing difficulties, chest tightness or swelling of the mouth or throat, you are going to require emergency medical treatment. Treatments can include (depending on severity):
- Cool compresses as well as baths (with cool water and baking soda) can provide pain and itching relief.
- Anti-inflammatory medicines (corticosteroids)
- Ranitidine (Zantac)
- Terbutaline (a bronchodilator, which can help with breathing problems)
- In severe cases, a breathing tube may be used.
Anaphylaxis is a severe, sometimes life-threatening allergic reaction that often involves hives.
Anaphylaxis can be caused by allergens or triggers. Common allergens or triggers include:
- Food as well as food additives. These many include eggs, seafood, peanuts, milk, fish, nuts and shellfish.
- Bee, hornet, wasp, yellow jacket or fire ant bites or stings.
- Medications (often including seizure medications, antibiotics and muscle relaxants)
- Latex products including medical gloves, condoms and medical tubing
- Dyes used during x-ray procedures and other medical tests.
Risk Factors for Anaphylaxis:
There are a number of factors that can increase your chances of going into anaphylaxis shock. These factors include:
- A history of eczema, asthma or hay fever.
- Prior allergic reactions even if there mild allergic reactions.
- Children with medical conditions including urogenitial defects and spina bifida. This is because these children may be at an increased risk of a latex allergy due to heavy latex exposure during many surgeries that are often required to treat these conditions.
Symptoms of Anaphylaxis:
If you experience anaphylaxis, you will likely experience symptoms within a few minutes to a few hours. Symptoms can range from very mild to severe and can include:
- Redness, stinging or burning of the face, eyes, hands or mouth
- Low blood pressure
- Severe respiratory distress
- Chest tightness
- Shortness of breath
- Nausea, vomiting, cramping or diarrhea
- Obstruction of the mouth, nose or throat
- Heart Arrhythmias
Treatment of Anaphylaxis:
Hives related to anaphylaxis require immediate medical attention. Treatment for this condition may include:
- Cardiopulmonary resuscitation (or CPR) in severe cases
- Mechanical ventilation
- Intravenous fluids
- Bronchodilators to help improving breathing function
- Epinephrine (or adrenaline) injections. These make blood vessels constrict which helps to relax the airways, stop hives, reduce itching and relieves any gastrointestinal problems.
Types of Hives
These are hives that usually last less than three weeks. They are most frequently the result of adverse reactions to food, medications or infections. You may also find yourself with acute urticaria as the result of an internal disease or from an insect bite. The foods that most commonly cause these types of hives include nuts, fish, chocolate, tomatoes, fresh berries, milk and eggs. Food additives and preservatives can also lead to acute urticaria. It is important to remember that fresh foods are more likely to cause hives than well-cooked foods. There are a number of medications that can cause hives. Aspirin, non-steroidal anti-inflammatory medications (NSAIDS), ACE inhibitors (blood pressure medication) and painkillers (like codeine) can all cause acute urticaria.
Chronic Urticaria and Angiodema.
These hives last six weeks are more. Your doctor may have a more difficult time diagnosing these hives than other forms of hives (such as acute urticaria). For many people who experience chronic urticaria, the cause of their hives may never be known. Chronic urticaria and angioedema can affect your internal organs. Your lungs, gastrointestinal tract and muscles can all be affected. Symptoms of these types of hives can include vomiting, diarrhea, shortness of breath and muscle soreness.
These types of hives are caused by direct physical stimulation of your skin. Elements that can directly affect your skin may include sun exposure, heat, cold, sweating, exercise, pressure or vibration. Hives usually occur in the exact location your skin has been stimulated. Physical urticaria rarely occurs on a portion of your body that has not been stimulated. These hives usually appear within one hour of stimulation.
These hives are hives that form as the result of firmly stroking or scratching your skin. These hives may develop in conjunction with any form of urticaria.
Treatment Options for Hives
If the symptoms that accompany your hives are mild, they often go away on their own and will not require any further medical attention. In many cases, hives as well as angioedema will clear up on its own. If you experience intense itching, pain or persistent symptoms, treatment can help.
Treatment for hives as well as angioedema largely centers around antihistamine medications that are designed to reduce swelling, itching and pain that is sometimes association with hives. If you are experiencing severe hives, your doctor may prescribe an oral corticosteroid drug (like prednisone). An oral corticosteroid drug can help to reduce swelling, itching and redness.
Antihistamines. There are a number of different antihistamines. Antihistamines are broken into two different categories. These categories include first-generation and second-generation medications. Classifications are based on their chemistry and common side effects. Drugs in each category may be prescription or over-the-counter.
- Second-generation antihistamines. Second generation antihistamines may also be referred to as newer antihistamines. These drugs are less likely to cause drowsiness or reduce your reaction time during activities like driving. Second generation antihistamines do not affect you as much mentally or physically as older medications may have. Examples of over-the-counter second generation antihistamines include Loratadine (Claritin or Alavert) and Cetirizine (Zyrtect). Prescription medications may include Desloratadine (Clarinex), Fexofenadien (Allegra) and Levocetirizine (Xyzal).
- First generation antihistamines. First generation antihistamine medications are also referred to as older antihistamines. These pills tend to make you drowsy and slow down your reaction times. This can make driving, operating machinery or performing other physical tasks a challenge. Other side effects associated with these older medications may include dry mouth, vision problems, difficulty passing urine or constipation. However, these drugs are often deemed to be more helpful for people with more severe hives or with angioedema. This is because they can help to reduce significant swelling of your tongue, throat and face. These medications can also help you to sleep better should your symptoms affect your sleeping habits. Over-the-counter first generation antihistamines can include Diphenhydramine (Benadryl) and Chlorphenirmine (Chlor-Trimeton). A commonly used first generation prescription antihistamine is Hydroxyzine (Vistaril).
Medications for Hereditary Angioedema:
Generally speaking, oral corticosteroids and antihistamine medications commonly used to treat angioedema and hives are not effective in treating hereditary angioedema. Medications that are used to treat this condition are often used long-term. These medications often contain androgens (male hormones) to help regulate levels of blood protein. As of 2011, the Food and Drug Administration (FDA) has approved a number of medications designed to specifically target blood proteins and their functions. These medications include:
- Cinryze and Berinert. These are two treatment methods that are derived from donated human blood plasma. Both of these prescription medications provide C1 esterase inhibitor, which is a blood protein that is often inadequate or lacking in patients who have been diagnosed with hereditary angioedema. Cinryze has been FDA approved for treatment of hereditary angioedema in adults and adolescents. This medication is given by injection into a vein every few days. You can be trained by a healthcare professional to self-administer the drug in the comforts of your own home. Berinert is another prescription medication used to treat hereditary angioedema attacks that affect the face and abdomen. This medication must be given during an attack and requires a medical professional to receive the injection.
- Ecallantide (or Kalbitor). This medication is a protein which is derived from yeast. It is designed to block the activity of a blood protein known as kallikrein, which plays a key role in the development of hereditary angioedema. It is currently approved for use in adolescents as well as adults. Ecallantide is given as a subcutaneous injection (under the skin) and must be given by your health care provider.
Home Treatments and Remedies For Hives
If you experience symptoms of mild hives or mild angioedema, there are numerous treatment options you can try in the comforts of your own home.
- Pay close attention to what may be causing your hives. If you notice you develop hives after eating a certain type of food (such as shellfish), avoid this food.
- Try an over-the-counter antihistamine to help relieve itching and pain associated with hives and angioedema. Over-the-counter antihistamines can include Claritin, Zyrtec and Benadryl, for example.
- Apply cold and wet compresses to the affected area of your skin. This can not only help soothe your skin, but it can prevent you from scratching and further irritating itchy skin.
- Take a bath. Sprinkle a few tablespoons of baking soda, uncooked oatmeal or colloidal oatmeal into your bath tub. A cool, oatmeal bath can help to relieve your symptoms.
- Watch what you wear while experiencing hives. Wear loose, cotton and smooth-textured clothing to help prevent irritation. Tight, rough, scratchy or clothing made from wool may irritate your skin.
Chronic Hives and Vitamin D Deficiency
In 2011, a University of Nebraska Medical research study revealed some interesting new research when it comes to chronic hives. The University of Nebraska Medical Center has determined that individuals with chronic hives may benefit greatly from supplementing vitamin D in their diet. Research suggests that medical professionals should consider screening patients with chronic hives for vitamin D deficiencies.
Dr. Jill Poole, an assistant professor at the UNMC Department of Internal Medicine, was the lead investigator on this study. Dr Poole indicates that chronic hives can be frustrating for patients. She also indicates that given the health benefits and lack of side effects when it comes to vitamin D should be taken into consideration when treating chronic hives. There is no harm in taking vitamin D as directed by a healthcare provider. Vitamin D is relatively inexpensive and should be taken in 1,000 to 2,000 IU (international units) daily.
To be considered a patient with chronic hives, you must have outbreaks of hives at least three times per week and they should last longer than six weeks. Your hives should be red, itchy welts that can also lead to breathing difficulties.
The University of Nebraska Medical Center conducted a small research study on 25 patients with chronic hives as well as nasal allergies. Researchers found that patients with chronic hives had significantly reduced levels of vitamin D in their blood stream. Nearly half of these patients were considered to be deficient in vitamin D.
Vitamin D deficiencies are also common in a number of medical conditions such as autoimmune diseases, cancer, cardiovascular disease, hypertension, osteoporosis and occasional death. Vitamin D has also been proven effective in treating other skin conditions, such as eczema.
While this research study is small, it shows promise. Dr. Poole indicates more research is necessary to better understand the effects of Vitamin D in patients with chronic hives.
When to Seek Medical Attention
Mild hives as well as angioedema usually are not threatening. Mild cases normally go away on their own or can be treated at home.
You should see a doctor if your hives or angioedema are not responding to home treatment, if you have severe discomfort or if your symptoms last for more than a few days.
There are cases of hives and angioedema that require immediate medical attention. Seek emergency medical treatment if you are lightheaded, have trouble breathing, experience chest tightness or you can feel your throat swelling.
Visiting with Your Doctor
If you experience mild hives frequently, you may want to make a trip to your primary care doctor. Here your doctor may examine any welts or swelling that is currently present on your body. Your doctor will also conduct a thorough medical history to identify possible causes of your hives. The physical examination along with a medical history can sometimes solve the mystery of your hives. Your doctor is likely to ask you questions focused on your eating habits, any medications you may take and environmental factors (Do you work outdoors? Do you have animals?).
Your doctor may recommend that you keep a detailed food dairy to help diagnose your hives. If your medical history and a physical examination are not enough to determine the causes of your hives, your doctor may opt to have you receive an allergy skin test.
An allergy skin test may involve a puncture, prick or scratch test. During this test, tiny purified allergen extract drops are pricked or scratched into the surface of your skin. This type of allergy test is normally performed when your doctor suspects allergies to animal dander, food, penicillin, pollen or insect venom.
Another test your doctor may order is known as an intradermal (or intracutaneuous) test. During this test, purified allergen extracts are injected into the skin of your arm. This test is most commonly performed when a doctor believes you are allergic to a specific irritant even when you have had a negative puncture test.
For suspected hereditary angioedema, a blood test may be ordered. This test will test for levels and functioning of specific blood proteins.