Hives, also called urticaria, is a raised, itchy area of skin that is usually a sign of an allergic reaction. The allergy may be to food or medications, but usually the cause of the allergy (the allergen) is unknown. Read more: Hives (Urticaria) Article
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Rosacea, Acne, Shingles, Covid-19 Rashes: Common Adult Skin Diseases
Learn to spot and treat skin conditions commonly found in adults such as acne, Covid-19 rashes, eczema, shingles, psoriasis,...
Bad Bugs: Identify Insects and Bug Bites
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Common Childhood Skin Disorders
What are the most common skin rashes in children? Learn about childhood eczema, ring worm, chicken pox and more. Get the facts on...
Out-of-Control Allergy Symptoms: Treatment Relief in Pictures
Learn 10 signs your allergies are out of control. See these surprising allergy symptoms and find out how to get relief for...
10 Worst Cities for Spring Allergies With Pictures
See pictures of the top 10 "spring allergy capitals", according to the Asthma and Allergy Foundation of America (AAFA). From...
Picture of Erythema Multiforme 1
This disorder is termed multiforme because the morphology of its lesions is so variable. See a picture of Erythema Multiforme...
Picture of Erythema Multiforme 2
Erythema multiforme tends to be acral in distribution, and the dorsum of the hand is a particularly common location. See a...
Picture of Skin
The skin is the largest organ of the body, with a total area of about 20 square feet. See a picture of the Skin and learn more...
Picture of Erythema Multiforme Minor
Polycyclic target lesions with alternating rings of erythema and dusky desquamation on the arm. See a picture of Erythema...
Picture of Urticaria
This is a close-up view of wheals with white-to-light-pink color centrally and peripheral erythema. See a picture of Urticaria...
IMAGESSee pictures of allergic skin disorders such as eczema, contact dermatitis and more caused by allergies See Images
Related Disease Conditions
Flea Bites (In Humans)
Flea bites are caused by the parasitic insect, the flea. The most common species of flea in the US is the cat flea, Ctenocephalides felis. Signs and symptoms of flea bites in humans include itching, hives, a rash with bumps, red spots with a "halo," and swelling around the bite. Treatment for flea bites includes over-the-counter medicine and natural and home remedies to relieve and soothe itching and inflammation. The redness of a flea bite can last from a few hours to a several days.
The word "rash" means an outbreak of red bumps on the body. The way people use this term, "a rash" can refer to many different skin conditions. The most common of these are scaly patches of skin and red, itchy bumps or patches all over the place.
Low Blood Pressure (Hypotension)
Low blood pressure, also referred to as hypotension, is blood pressure that is so low that it causes symptoms or signs due to the low flow of blood through the arteries and veins. Some of the symptoms of low blood pressure include light-headedness, dizziness, and fainting if not enough blood is getting to the brain. Diseases and medications can also cause low blood pressure. When the flow of blood is too low to deliver enough oxygen and nutrients to vital organs such as the brain, heart, and kidneys; the organs do not function normally and may be permanently damaged.
Itch (Itching or Pruritus)
Itching can be a common problem. Itches can be localized or generalized. There are many causes of itching to include: infection (jock itch, vaginal itch), disease (hyperthyroidism, liver or kidney), reactions to drugs, and skin infestations (pubic or body lice). Treatment for itching varies depending on the cause of the itch.
Eczema is a general term for many types dermatitis (skin inflammation). Atopic dermatitis is the most common of the many types of eczema. Other types of eczema include: contact eczema, allergic contact eczema, seborrheic eczema, nummular eczema, stasis dermatitis, and dyshidrotic eczema.
An allergy refers to a misguided reaction by our immune system in response to bodily contact with certain foreign substances. When these allergens come in contact with the body, it causes the immune system to develop an allergic reaction in people who are allergic to it. It is estimated that 50 million North Americans are affected by allergic conditions. The parts of the body that are prone to react to allergies include the eyes, nose, lungs, skin, and stomach. Common allergic disorders include hay fever, asthma, allergic eyes, allergic eczema, hives, and allergic shock.
Eczema refers to skin inflammation. There are many different types of eczema that produce symptoms and signs that range from oozing blisters to crusty plaques of skin. Treatment varies depending upon the type of eczema the person has.
Stress occurs when forces from the outside world impinge on the individual. Stress is a normal part of life. However, over-stress, can be harmful. There is now speculation, as well as some evidence, that points to the abnormal stress responses as being involved in causing various diseases or conditions.
The most common cause of a black eye is a trauma injury to the face or head. Most black eyes are minor and heal on their own; however, some may lead to significant injury. In addition to trauma to the face, cosmetic surgery can cause a black eye(s) as a side effect. Learn when to seek immediate medical care for a black eye.
What Is the Difference Between HIV-1 and HIV-2?
There are two main types of the human immunodeficiency virus (HIV), HIV-1 and HIV-2. HIV-1 is the most common type of HIV and accounts for 95% of all infections, whereas HIV-2 is relatively uncommon and less infectious. HIV-2 is mainly concentrated in West Africa, is less deadly and progresses more slowly.
Anaphylaxis is a serious allergic reaction that affects a number of different areas of the body at one time, and can be fatal. Causes of anaphylaxis can be food allergy, latex allergy, allergy to insect or but stings/bites, asthma, or other materials or conditions. Symptoms include flushing, itching, hives, anxiety, rapid or irregular pulse. Severe symptoms may be throat and tongue swelling, swallowing, and difficulty breathing. Some disorders appear similar to anaphylaxis such as fainting, panic attacks, blood clots in the lungs, heart attacks, and septic shock. If you think that you may be having an anaphylactic reaction, seek emergency care or call 911 immediately.
Fragrances and preservatives in cosmetics may cause allergic reactions in some people. Symptoms include redness, itching, and swelling after the product comes in contact with the person's skin. Treatment typically involves the use of over-the-counter cortisone creams.
What Is the Best Treatment for Urticaria?
Learn what medical treatments can help ease your urticaria symptoms and speed up your recovery.
How Do You Get Rid of Hives Fast?
Learn what medical treatments can help ease your hives and speed up your recovery.
What Are the Four Stages of HIV?
The World Health Organization (WHO) classifies human immunodeficiency virus (HIV) into four stages. Stage 1 (HIV infection): The CD4+ cell count is at least 500 cells per microliter. Stage 2 (HIV infection): The CD4+ cell count is 350 to 499. Stage 3 (advanced HIV disease or AHD): The CD4+ cell count is 200 to 349. Stage 4 (Acquired immunodeficiency syndrome [AIDS]): The CD4+ cell count is less than 200.
How to Get Rid of Hives: 20 Ways
Hives or urticarias are red, itchy skin rashes triggered by food, medicine, or other irritants. They can vary from a few millimeters to several centimeters in diameters.
What Triggers Urticarial Vasculitis?
Urticarial vasculitis is a rare autoimmune disease. Learn the signs of urticarial vasculitis, what causes urticarial vasculitis, how doctors diagnose urticarial vasculitis, and what you can do to treat urticarial vasculitis.
The most common food allergies are to eggs, nuts, milk, peanuts, fish, shellfish, strawberries and tomatoes. Symptoms and signs of a food allergy reaction include nausea, vomiting, diarrhea, abdominal pain, itching, hives, eczema, asthma, lightheadedness, and anaphylaxis. Allergy skin tests, RAST, and ELISA tests may be used to diagnose a food allergy. Though dietary avoidance may be sufficient treatment for mild allergies, the use of an Epipen may be necessary for severe food allergies.
Insect Sting Allergies
The majority of stinging insects in the United States are from bees, yellow jackets, hornets, wasps, and fire ants. Severity of reactions to stings varies greatly. Avoidance and prompt treatment are essential. In selected cases, allergy injection therapy is highly effective.
Peanut allergies causes signs and symptoms that include hives, itching, redness, and a rash. Severe reactions may cause decreased blood pressure, lightheadedness, difficulty breathing, nausea, and behavioral changes. Someone with a peanut allergy should have an EpiPen with them at all times.
Hereditary Angioedema (HAE)
Hereditary angioedema or HAE is a genetic disease that causes swelling of the skin and tissues beneath it. Symptoms of HAE include shortness of breath, mood changes, laryngeal edema (a medical emergency), swelling of the hands and feet, muscle aches, and skin tingling. Treatment of HAE includes medication and avoidance of triggers.
Are Hives and Rash the Same Thing?
Learn how to tell the difference between a rash and hives and how to treat both.
Are Hives (Urticaria) Contagious?
Hives are not contagious are triggered by an allergic response to a substance. Symptoms and signs of hives include a raised, itchy red rash on the skin. An individual should seek medical care for hives if he or she develops dysphagia, wheezing, shortness of breath, or throat tightening.
Bug Bites and Stings
Bug bites and stings have been known to transmit insect-borne illnesses such as West Nile virus, Rocky Mountain spotted fever, and Lyme disease. Though most reactions to insect bites and stings are mild, some reactions may be life-threatening. Preventing bug bites and stings with insect repellant, wearing the proper protective attire, and not wearing heavily scented perfumes when in grassy, wooded, and brushy areas is key.
What Is Microsporidiosis?
Microsporidiosis is an infection caused by the microsporidia parasite. The disease is uncommon in people with normal immune systems. Symptoms in people with immune deficiency include diarrhea, malabsorption, gallbladder disease, cough, labored breathing, urinary tract infection, bowel perforation and keratoconjunctivitis. Microsporidiosis treatment depends on the site of infection and the species of microsporidia involved.
What Causes Angioedema?
What is angioedema? Angioedema is a form of swelling that occurs under the skin. Learn what causes angioedema, its signs and symptoms, how doctors diagnose it, when to see a doctor, and ways to treat this condition.
What Is the Best Treatment for a Jellyfish Sting?
Jellyfish are the most common creatures found in seawater around the world. Jellyfish tentacles have stinging cells called nematocysts that secrete a poisonous substance (venom). The best treatment for jellyfish stings includes rinsing the area with water or vinegar, removing the tentacles, soaking the affected area in hot water, taking medications to ease itching and pain and seeking medical attention, if necessary.
First Aid and CPR
First aid is providing medical assistance to someone a sick or injured person. The type of first aid depends on their condition. Preparedness is key to first aid, like having basic medical emergency kits in your home, car, boat, or RV. Many minor injuries may require first aid, including cuts, puncture wounds, sprains, strains, and nosebleeds. Examples of more critical first aid emergencies include heart attacks, strokes, seizures, and heatstroke.
Drug Allergy (Medication Allergy)
Drug or medication allergies are caused when the immune system mistakenly creates an immune response to a medication. Symptoms of a drug allergic reaction include hives, rash, itchy skin or eyes, dizziness, nausea, diarrhea, fainting, and anxiety. The most common drugs that people are allergic to include penicillins and penicillin type drugs, sulfa drugs, insulin, and iodine. Treatment may involve antihistamines or corticosteroids. An EpiPen may be used for life-threatening anaphylactic symptoms.
What Are the Main Causes of Urticaria (Hives)?
Hives are mostly an allergic reaction, appearing quickly and disappearing as fast. Learn what causes them, when to see a doctor and how to avoid them.
What Causes Urticaria Pigmentosa?
Urticaria pigmentosa is a skin condition that causes intense itching and patches of darker skin. Learn the signs of Urticaria Pigmentosa, what causes it, how doctors diagnose it, and the treatment options you have.
What Are the Main Causes of Skin Rashes in Kids?
Why does my child have a skin rash? Find out what to do if your child has a skin rash and why it might occur.
Is There a Cure for Aquagenic Urticaria?
Aquagenic urticaria or aquagenic pruritus is a rare dermatological condition. There is no cure for aquagenic pruritus, but it is treated with oral medications, phototherapies, TENS, topical creams and by adding sodium bicarbonate to bath water.
What Is Causing My Hives?
Hives, medically known as urticaria, are common rashes that anyone can get at any point in their lives. They can happen only once in your life, keep happening often, or stay longer (chronic) for more than 6 weeks.
How Is Angioedema Treated?
Learn what medical treatments can help treat your angioedema symptoms and help you manage this condition.
Local ResourcesFind a local Dermatologist in your town
Treatment & Diagnosis
Medications & Supplements
- Nonsteroidal Antiinflammatory Drugs (NSAIDs)
- prednisone (Prednisone Intensol, Rayos) Corticosteroid
- Biologics (Biologic Drug Class)
- hydroxyzine (Vistaril)
- ibuprofen (Advil, Motrin, Nuprin)
- Antihistamines (Oral)
- diphenhydramine, Benadryl
- fexofenadine - oral, Allegra
- loratadine - oral, Claritin
- fexofenadine 24-hour tablet - oral, Allegra
- diphenhydramine - injection, Benadryl
- cetirizine - oral, Zyrtec
- diphenhydramine - oral, Benadryl, Genahist, Sominex, U
- desloratadine - oral, Clarinex
- loratadine liquid - oral, Claritin
- loratadine dispersible tablet - oral, Alavert ODT, Claritin RediTabs
- desloratadine dispersible tablet - oral, Clarinex Reditabs
- Antihistamine Shots (Injections)
- cetirizine liquid - oral, Zyrtec
- Side Effects of Xyzal (levocetirizine dihydrochloride)
- Nasal Decongestants
- amitriptyline (Elavil, Endep)
- montelukast, Singulair
- cyproheptadine (Periactin)
- prednisolone (Orapred, Pediapred)
- aluminum hydrochloride (Drisol, Certain Dri, Hydrosol, Xerac AC, Hypercare Solution)
- loratadine, Claritin, Claritin RediTabs, Alavert, Claritin Hives Relief, Children's Claritin
- cimetidine, Tagamet HB
- ranitidine, Zantac
- cetirizine (Zyrtec, Zyrtec Allergy, Zyrtec Hives)
- nortriptyline (Pamelor)
- Lysteda (tranexamic acid)
- pramoxine (Itch-X, PrameGel, Orax, Sarna Sensitive, and Others)
- EpiPen (epinephrine auto-injector)
- loratadine and pseudoephedrine (Alavert Allergy & Sinus, Claritin-D, Claritin-D 24 hour)
- fexofenadine (Allegra, Mucinex Allergy)
- clemastine - oral, Tavist
- What Are NRTIs in Antiretroviral Therapy For HIV Infection?
- Xyzal (levocetirizine dihydrochloride)
- Side Effects of Clarinex (desloratadine)
- desloratadine (Clarinex, Clarinex Reditabs)
- What Are the Single-Tablet ART Regimens for HIV Infection?
- Quzyttir (cetirizine)
- Tipranavir (Aptivus)
- Tybost (cobicistat)
Prevention & Wellness
- Is It Allergies or COVID? How to Tell the Difference
- Antihistamines Linked to Delayed Care for Severe Allergic Reaction: Study
- Ditch the Itch: Researchers Find New Drug to Fight Hives
- Egg Allergy? Don't Let That Stop You From Getting Vaccinated
- Nearly 4 Percent of Americans Suffer From Food Allergies
- Daffodils, Margaritas and Other Surprise Skin Dangers
- Got an Itch? Use These Tips for Relief -- and Don't Scratch
- Doctors Talk About Getting Peanuts Into a Baby's Diet, Which May Cut Allergies
- Is Non-Celiac Gluten Sensitivity Real?
- Think You're Allergic to Penicillin? Maybe Not
- Health Tip: Are You Allergic to Your Pet?
- Health Tip: Easing Hives
- Dermatologist Offers Advice on Treating Kids' Hives
- Health Tip: What Causes Hives?
- Asthma Drug May Help Those With Chronic Hives
- Gradual Exposure to Peanuts May Help Some Allergic Kids
- FDA Advisers: Pill for Ragweed Allergy Safe and Effective
- FDA Panel Considers First Pill for Ragweed Allergy
- Stocking Epinephrine in Schools Might Save Lives
- Gelatin Allergy May Mean Extra Care Is Needed With Flu Shot
- Egg Allergy No Obstacle to Child's Flu Shot, CDC Says
- New Choices for Seasonal Flu Vaccines
- Skin Allergies Can Flare Up in Summer Heat
- Watch Out for Backyard Allergy Triggers
- Health Tip: Avoid Bug Bites
- Lone Star Tick Bite Might Trigger Red Meat Allergy: Study
- Son's Real-Life Drama Leads Comedy Queen to Medical Role
- That May Not Be a Cold, Could Be Fall Allergies
- Untreated Food Allergies More Likely in Poor, Minority Kids
- FDA Warns Against Use of Diarrhea Drug From El Salvador
- For Colorado Family, It's Allergies All Around
- Certain Tick Bites Might Spur Red Meat Allergy
- Food Allergy Reactions in Kids Undertreated
- Summer's Heat May Enflame Hives
- Many Medical Tests, Procedures Not Always Needed
- Hospitalizations Up for Severe Skin Swelling
- Many Asthmatics Do Well on Food-Allergy Tests, Study Finds
- More People Need Training in Lifesaving Epinephrine Use, Advocates Say
- Bedbugs: Why They're Back
- Pork-Cat Syndrome an Under-Recognized Allergy
- Health Tip: When Exercise Causes Hives
- Survey: Two-Thirds of Americans Plan to Get Flu Vaccine
- Little Insects, Big Allergic Reactions
- Insect Stings Hold Deadly Risk for Some
- Xolair May Treat Milk Allergy in Kids
- FAQ: Pesky Rashes From Plants
- Health Tip: Coping With Hives
- Health Tip: What May Be Behind Hives
- Kids With Food Allergies May Need 2 EpiPens