Dandelion Chronic hives and swelling
Chronic hives, also called chronic urticaria, are itchy raised welts that come and go for more than six weeks, sometimes with deeper swelling called angioedema. An allergist can look for causes and triggers and discuss ways to bring symptoms under better control.
Common signs people are referred for
A doctor may refer you to an allergist if you or your child have:
- Hives that appear most days, or on and off, for more than six weeks
- Swelling of the eyelids, lips, face, hands or feet
- Hives that seem linked to heat, cold, pressure, exercise or sun
- Hives that continue despite the antihistamines you already take
- Itching or hives that disturb sleep, school or work
- Worry that a food is causing the hives
These are reasons a doctor may suggest an allergist visit. They are not a way to diagnose yourself or your child.
How an allergist assesses it
Your allergist will ask when the hives started, how long each one lasts, whether they leave a mark, and whether swelling occurs. They will also ask about triggers such as heat, cold, pressure and exercise, recent illnesses, medications and other health conditions. Photos of outbreaks are very helpful because hives often fade before the visit.
Chronic hives are usually not caused by a food allergy, and in many people no outside trigger is found, so testing is not always needed. When the history suggests an allergic cause, your allergist may use allergy skin testing or arrange blood tests. A positive test alone does not confirm that something is causing your hives, so results are read together with your history. You can read more on our chronic hives service page.
Your clinic will tell you before the visit what, if anything, needs to be paused. Please do not pause any medication unless the clinic or your own doctor has told you to.
Treatment and management options
Treatment depends on how severe the hives are and how much they affect daily life. Options may include:
- Antihistamines as directed by your own physician or allergist, which may be adjusted over time
- Identifying and avoiding factors that can make hives worse
- Additional medications prescribed when symptoms stay uncontrolled
- Biologic treatments, which may be considered for some patients
Your allergist will explain which options may suit you and how to track how you are doing.
When to seek emergency care
Hives on their own are generally not dangerous. However, swelling of the throat or tongue, trouble breathing, faintness or other signs of a severe allergic reaction need emergency care. Call 911. If an epinephrine auto-injector has been prescribed, use it as you have been instructed.
Children and adults
Our pediatric and adult allergists see all ages. Hives can affect children, teens and adults, and the assessment is adjusted to the age of the patient.
Frequently asked questions
Are chronic hives caused by a food allergy?
Usually not. Chronic hives most often occur without an outside trigger being found. If your history suggests a food or medication may be involved, your allergist will talk with you about it.
How long do chronic hives last?
The course varies a lot from person to person, so there is no single answer. Your allergist can talk with you about what to expect in your situation.
Are hives contagious?
No. Hives are not contagious and cannot be passed from one person to another.
Will I need testing for chronic hives?
Sometimes. Testing is arranged when your history suggests it would be helpful, and your allergist will explain the reasons.
Related reading
Getting an assessment
For patients
Patients cannot refer themselves. Ask your family doctor or a walk-in clinic to fax a referral to 416 850 9993, and our team will contact you to book.
How referrals workFor physicians
Send a referral through our secure online form, or read the referral guide first.
Open the referral formLast updated: October 2026Prepared by: Dandelion Allergy CentreGeneral information only, not medical advice. Your allergist's instructions take priority over anything on this page.