Painless swelling under the skin, triggered by an allergy to animal dander, pollen, drugs, venom, food, or medicine.

Avoid things known to trigger angioedema. Take the type of antihistamine that you can buy without a prescription. Apply a cool, wet cloth to the swollen area.

See a healthcare professional right away for:

• Throat swelling
• Trouble breathing

Make an appointment for medical care if the condition:

• Persists or worsens