Adult Hives Causes: Triggers, Conditions and Medicines to Consider
Hives in adults can have many causes, and in a large share of cases, especially long-lasting ones, no cause is ever found. Understanding the most common categories helps you and your doctor look in the right places.
Most Common Triggers in Adults
- Infections: colds, flu, strep, urinary infections and COVID-19
- Medications: NSAIDs, antibiotics, ACE inhibitors, opioids
- Foods: shellfish, nuts, eggs, fish, milk
- Physical triggers: cold, heat, pressure, sunlight, exercise
- Stings and bites
Underlying Medical Conditions
Chronic hives are associated with autoimmune disease, particularly thyroid disease. See autoimmune hives and thyroid and hives. Rarely, hives signal conditions such as lupus or blood disorders.
Lifestyle and Stress
Stress, alcohol, hot environments and lack of sleep can worsen hives. See stress hives.
Finding Your Cause
Keep a diary of foods, medicines, activities and symptoms. Bring it to your doctor, who will decide whether testing is useful. For a full overview, see causes of hives.
When to Call 911
Treat these symptoms as an emergency and call 911 if hives appear together with shortness of breath, a hoarse voice or trouble swallowing, swelling of the face, tongue or throat, a racing heartbeat, fainting, or vomiting and severe stomach cramps soon after a food, medication or insect sting. Do not wait to see whether they pass.
When to See a Doctor
See a doctor if your symptoms last more than a few days, keep coming back, cover large areas, or interfere with sleep or daily life. Dr. Tiffany Young and the Hives Treatment Center in San Francisco provide online and in-person care for hives in adults.
Frequently Asked Questions About Causes of Hives in Adults
Why did I suddenly get hives as an adult?
Often an infection, medicine or unknown trigger; sometimes new onset chronic hives.
Can hives be a sign of cancer?
It is rare. Most hives are not related to cancer.
Should adults get allergy testing?
Only when a trigger is suspected.
Get Relief for Your Hives
A specialist can help find a trigger or control hives without one. Visit our hives treatment page to see the latest treatment options for your outbreak.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis or treatment. If you think you are having a medical emergency, call 911.
