What Is Chronic Spontaneous Urticaria (Hives)? Symptoms, Causes, Diagnosis, Treatment, and Prevention

You’re probably familiar with hives — intensely itchy welts on the surface of the skin.
For most people, these welts disappear in 24 hours or less, without leaving a mark. But when the welts appear spontaneously (with no known cause) and linger for longer than six weeks, they’re known as chronic spontaneous urticaria (or chronic idiopathic urticaria).
Types of Urticaria
- Acute Spontaneous Urticaria Hives that occur spontaneously but fade within six weeks.
- Chronic Spontaneous Urticaria Hives that occur spontaneously and linger for six weeks or longer, either continuously or intermittently. This is also known as chronic urticaria and chronic idiopathic urticaria.
- Chronic Inducible Urticaria Hives that occur in response to a trigger, such as heat, exercise, or scratching.
Signs and Symptoms of Chronic Spontaneous Urticaria
The symptoms of chronic spontaneous urticaria include:
- Patches of welts (called wheals) on the body, especially on the arms, back, chest, face, and legs
- Itchiness (pruritus)
- Painful swelling (angioedema) around the cheeks, eyes, or lips
These welts may appear red or pink on white skin. On brown or Black skin, hives can appear the same color as the surrounding skin, purplish, or slightly darker or lighter in hue. When you press on the welt, it tends to “blanch,” or fade in color.
Causes and Risk Factors of Chronic Spontaneous Urticaria
Usually, there’s no known cause of chronic spontaneous urticaria, but hives may develop when a physical trigger like friction, pressure, heat or cold, or even sunlight activates certain cells in the immune system called mast cells.
When that happens, the skin releases chemicals such as histamine, a compound that causes itching and swelling.
- Cold or heat
- Medical conditions, such as autoimmune disease, infection, cancer, or allergies
- Pressure on the skin, from a backpack or bra strap
- Sunlight
- Vibration, such as jogging
While people often believe that hives are a response to stress, “Stress can lower the threshold for developing hives, but it’s not the underlying cause,” says Mark Aronica, MD, a physician who specializes in asthma and allergic disorders in the department of allergy and clinical immunology at Cleveland Clinic in Ohio.
Similarly, even though chronic hives are rarely triggered by allergies, people who have allergies are a little more likely to have an episode of chronic urticaria at some point in their lives, says Dr. Aronica.
How Is Chronic Spontaneous Urticaria Diagnosed?
In most cases, doctors evaluating a person with acute urticaria (lasting less than six weeks) make a diagnosis based solely on a physical exam and an assessment of symptoms.
But when hives become chronic (lasting longer than six weeks), physicians typically order a comprehensive medical workup.
A physician might perform a skin biopsy or order blood work if the hives are persistent or linked to additional symptoms, such as fever, individual hives that last for days at a time, or hives that are painful or associated with bruising.
Treatment and Medication Options for Chronic Spontaneous Urticaria
The treatment for chronic spontaneous urticaria can vary from person to person and often depends on the severity of the hives. While anti-itch medications are often the first-line treatment option, some people may not need to take anything at all.
“If I have a patient who is having intermittent hives — they’re getting an outbreak once a week or a couple times a month — taking a medication every single day for this may not be the appropriate strategy,” says Aronica.
Medication Options
Part of the decision to treat or not treat chronic hives largely depends on the person, says Aronica. “That decision can depend on how the hives are affecting [the person] and what they want to accomplish.”
The standard therapy for people having frequent episodes of chronic hives is a long-acting, nonsedating antihistamine, many of which are available over the counter, including loratadine (Claritin) and fexofenadine (Allegra).
Histamine (H2) Blockers Also called H2 receptor antagonists, histamine blockers are injected or taken orally. Examples include cimetidine (Tagamet HB) and famotidine (Pepcid).
Anti-Inflammation Medications Oral corticosteroids, such as prednisone, can help with symptoms such as discoloration, itching, and swelling but shouldn’t be used long term.
Asthma Drugs With Antihistamines These medications can help with hives and itching in some people when used together with antihistamines. Examples are montelukast (Singulair) and zafirlukast (Accolate).
Monoclonal Antibodies The drugs omalizumab (Xolair) and dupilumab (Dupixent) may be given as injections for difficult-to-treat chronic hives.
Immune-Suppressing Drugs These medications — including cyclosporine (Neoral, Sandimmune), methotrexate, and tacrolimus (Prograf) — work by suppressing the immune system and are usually limited to short-term use.
Prevention of Chronic Spontatenous Urticaria
Because no one knows what causes chronic idiopathic urticaria, there is no clear way to prevent the condition.
Lifestyle Changes for Chronic Spontaneous Urticaria
- Wear comfortable, loose clothing.
- Avoid soaps and lotions with harsh chemicals.
- Take a soothing bath and then apply fragrance-free lotion or anti-itch cream to your skin.
Should You Try a Low-Histamine Diet?
Some foods — such as seafood, fermented foods (aged cheeses, dry sausage, fermented soy), tomatoes, eggplant, spinach, and avocado — contain higher levels of histamine than others. So it’s thought that limiting or avoiding these foods might help alleviate the symptoms of chronic spontaneous urticaria. But it’s not known for sure if there’s an actual connection or not.
“The data is a little mixed,” says Aronica. But “I tell them if that helps them, that’s fine with me.”
Once the symptoms improve, the person doesn’t necessarily have to continue avoiding those foods, says Aronica.
How Long Does Chronic Spontaneous Urticaria Last?
Usually, chronic spontaneous urticaria lasts from several months to about a year. Up to 80 percent of people achieving remission within the first 12 months of developing symptoms, but some cases can last for three to five years.
Chronic urticaria is often a “one and done” situation, says Aronica. “That ‘one time’ can last for a couple months or couple years,” he says, “but then they never experience it again.”
Complications of Chronic Spontaneous Urticaria
The complications of chronic spontaneous urticaria can include:
- Angioedema The eyes, lips, and tongue can swell. Rarely, the throat also swells, which could cause difficulty breathing and may be life threatening, says Aronica.
- Anxiety and Depression Chronic hives can be very uncomfortable — and highly visible — which can cause emotional distress for some people, says Aronica.
- Pruritus The intense itching from chronic hives can affect quality of life.
Research and Statistics: Who Has Chronic Spontaneous Urticaria?
Related Conditions and Causes of Chronic Idiopathic Urticaria
A small subset of people with chronic urticaria may develop an autoimmune disorder, though the risk is small, says Aronica.
The Takeaway
- Chronic spontaneous urticaria can cause itchy welts to appear on the skin. There’s no known cause for why they appear.
- Some treatments for chronic spontaneous urticaria include antihistamines, immune-suppressing medications, and monoclonal antibodies.
- For many people, chronic spontaneous urticaria often goes into remission within one year.
Resources We Trust
- Mayo Clinic: Chronic Hives
- Cleveland Clinic: Hives in Children
- American Academy of Dermatology Association: Hives: How to Get Relief at Home
- American College of Allergy, Asthma & Immunology: Hives
- Asthma and Allergy Foundation of America: Hives (Urticaria)
- Dabija D et al. Chronic Urticaria. StatPearls. April 17, 2023.
- Hives (Urticaria) and Angioedema Overview. American Academy of Allergy, Asthma & Immunology. June 2, 2024.
- Ludmann P. Hives: Signs and Symptoms. American Academy of Dermatology Association. May 30, 2024.
- Saini S. Patient Education: Hives (Urticaria) (Beyond the Basics). UpToDate. November 15, 2024.
- Chronic Hives. Mayo Clinic. October 1, 2024.
- Hives. Cleveland Clinic. October 14, 2022.
- What Is Chronic Urticaria? Allergy & Asthma Network.
- Novartis Receives FDA Approval for Rhapsido® (remibrutinib), the Only Oral, Targeted BTKi Treatment for Chronic Spontaneous Urticaria (CSU). Novartis. September 30, 2025.
- Ludmann P. Chronic Spontaneous Urticaria: Effective Treatment Possible. American Academy of Dermatology Association. December 6, 2024.
- Geissbühler Y et al. Incidence and Prevalence of Chronic Spontaneous Urticaria Among Adult and Pediatric Populations in the United States. Advances in Therapy. June 2025.
- Wertenteil S et al. Prevalence Estimates for Chronic Urticaria in the United States: A Sex- and Age-Adjusted Population Analysis. Journal of the American Academy of Dermatology. July 2019.

Jon E. Stahlman, MD
Medical Reviewer
Jon E. Stahlman, MD, has been a practicing allergist for more than 25 years. He is currently the section chief of allergy and immunology at Children’s Healthcare of Atlanta's Scottish Rite campus and the senior physician at The Allergy & Asthma Center in Atlanta. He served as the president of the Georgia Allergy Society, has been named a Castle Connolly Top Doctor, and was listed as a Top Doctor by Atlanta magazine. His research interests include new therapies for asthma and allergic rhinitis as well as the use of computerized monitoring of lung function.
He received his bachelor's and medical degrees from Emory University. He completed his pediatric residency at Boston Children’s Hospital and his fellowship in allergy and clinical immunology at Harvard University’s Boston Children’s Hospital and Brigham and Women’s Hospital. After his training, Dr. Stahlman conducted two years of clinical research at Boston Children’s Hospital and was part of the faculty at Harvard Medical School, where he taught medical students and allergy and immunology fellows.
Stahlman is board-certified and recertified in allergy and clinical immunology. He served as a principal investigator on phase 2 through 4 studies that are responsible for most of the U.S. Food and Drug Administration–approved therapies for allergies and asthma available today.
Outside of the office, he centers his interests around his wife and three daughters, coaching soccer for many years, and his hobbies include cycling and triathlons.

Becky Upham
Author
Becky Upham has worked throughout the health and wellness world for over 25 years. She's been a race director, a team recruiter for the Leukemia and Lymphoma Society, a salesperson for a major pharmaceutical company, a blogger for Moogfest, a communications manager for Mission Health, a fitness instructor, and a health coach.
Upham majored in English at the University of North Carolina and has a master's in English writing from Hollins University.
Upham enjoys teaching cycling classes, running, reading fiction, and making playlists.