Hives are itchy, raised, reddish or skin colored welts on the surface of the skin. Most common symptom of hives is itchiness. Oftentimes the itching starts before the welts appear. Sometimes along with excessive itchiness you will feel burning or stinging sensation. You can develop hives due to an allergic reaction to food or medications or as a response to stress. But sometimes they appear without a known reason (idiopathic or spontaneous hives). Hives can appear anywhere in the body, and they can vary in size. About 20% of the population will get hives at least one time in their lives. About 1% to 3% of the population has chronic hives. Hives can occur in anyone, from infants to older individuals. The medical term for hives is urticaria.
Types of hives (Urticaria)
Depending on how long they would last and what triggers them, hives can be divided into few categories.
What are the signs and symptoms of hives?
Hives can show up anywhere in your body. In many aspects, acute and chronic hives may look alike. Both types of hives share symptoms like:
- red, purple or skin color blotchy rash
- raised welts with lighter centers
- round, oval, or worm shaped rash
- can be as small as a fingertip or as big as a dinner plate.
- appear in clusters
- can be associated with the swelling around the eyes, cheeks, or lips causing puffiness (angioedema)
- shift sizes and shapes of the rash
Apart from the symptoms shared with the other types of hives, chronic hives have unique symptoms such as:
- flares triggered by heat, exercise, or stress
- symptoms persist for more than six weeks
- hives can recur often sometimes for months and years
Causes and triggers for hives
When your body get exposed to an allergen, your immune system responds by activating a special cell type called mast cells. When these cells go into action, they release chemicals including histamine. This is the same chemical that get released when you get allergies to pollen. When histamine is released into the small blood vessels, especially the ones closer to your skin surface, capillaries dilate and form welts. Histamine also cause excessive itching. There are multiple causes for the breakout of hives. Most common triggers are:
- food allergies (shellfish, milk, nuts, berries, etc.)
- insect stings and bites
- penicillin and other antibiotics
- allergy shots
- infections (hepatitis, strep throat, dental infections, other bacteria or viral infections)
- poison ivy
- pets and other animals
- sun exposure
- exposure to cold (snow or cold water)
- scratching (dermatographia)
- putting pressure on the skin for a long time such as sitting or wearing tight clothing
There are less common causes of hives such as exposure to water at any temperature (aquagenic urticaria), autoimmune diseases like celiac disease and rheumatoid arthritis, sweat or heat, vibration (vibratory urticaria), and friction.
When should I see a doctor for hives?
Typically most of the hives will go away with time. But if you have hives that last for more than a few days and/or symptoms get worse with time, you should see a healthcare provider. There are several prescription options available to treat chronic or severe hives such as:
- Anti-inflammatory drugs Typically prednisone is given to patients with chronic and/or severe hives. This is an oral steroid medication (corticosteroid) that can help reduce inflammation. As corticosteroids can have side effects, you should only use this medication for a short period of time as directed by a healthcare provider.
- Medication to control the pain If the pain and swelling associated with the hives don’t go away with over-the-counter medication, your doctor might prescribe a type of nonsteroidal, anti-inflammatory medication called leukotriene-receptor antagonists.
- Immune suppressors Hives are developed due to an over reaction of the immune system. When the over-the-counter antihistamines cannot reduce the symptoms, your doctor will prescribe drugs to calm down the immune system. These drugs can include but not limited to cyclosporine (Gengraf), tacrolimus (Prograf), hydroxychloroquine (Plaquenil), and mycophenolate (Cellcept).
- Blood protein controllers For some types of hives you might have to take drugs that can regulate certain proteins [e.g., amyloid A protein (3) and C-reactive protein (4)] in the blood that are associated with hives.
In some rare cases, along with hives there can be a possibility of developing anaphylaxis. It is a life-threatening whole body allergic reaction that causes breathing difficulty. Therefore, if you have difficulty in breathing, dizziness, tightening of the chest, swelling of the tongue, lips or face along with hives, you should immediately contact a healthcare provider.
Hives are itchy rashes typically fade away with time or with the use of over-the-counter medications. But sometimes, consultation of a dermatologist and the use of prescription medication is needed to treat chronic and/or severe hives. The staff at Saguaro Dermatology are dedicated to providing you with compassionate and quality health care to treat many skin conditions including hives. Our board-certified dermatologists along with our caring and experienced staff are always ready to help you at Saguaro Dermatology, with four convenient locations: Ahwatukee, Mesa, Phoenix, and Sun City West.