Angioedema: what it looks like and what to do

Angioedema is sudden swelling under the skin or mucous membrane. It usually shows up on the face, lips, tongue, throat, hands, or genitals. Sometimes it hurts, sometimes it’s just uncomfortable, but the biggest risk is when swelling hits the airway and you can’t breathe. Quick recognition and the right treatment make all the difference.

How angioedema happens — two main types

There are two common causes you need to know. The first is histamine-driven angioedema. This is the kind tied to allergies: insect stings, certain foods, or drug reactions. It often comes with hives, itching, and responds to antihistamines, steroids, and epinephrine if severe.

The second is bradykinin-driven angioedema. This includes hereditary angioedema (HAE) and angioedema caused by ACE inhibitor drugs. It usually doesn’t cause hives, and antihistamines or epinephrine won’t help. In these cases, specific treatments like C1-inhibitor concentrates, icatibant, or kallikrein inhibitors are needed.

Spotting danger and acting fast

Call emergency services or go to the ER right away if swelling affects the tongue, throat, or you have trouble breathing, swallowing, or a high-pitched sound when breathing (stridor). For allergy-related attacks, use an epinephrine auto-injector immediately if available, then seek care. For known HAE, follow your emergency plan — patients often carry specific meds for self-injection.

If angioedema starts after taking an ACE inhibitor (lisinopril, enalapril, etc.), stop the drug and contact your doctor. ACE-related angioedema can appear even after months or years on the medication. Do not restart the same drug. Your doctor may consider alternatives but will weigh risks carefully.

Diagnosing the cause matters. For suspected HAE, a simple blood test measures C4 and C1-inhibitor levels and function. Low C4 with abnormal C1-INH points to hereditary angioedema and changes long-term management: you may get preventive therapy like lanadelumab or an oral option called berotralstat.

Practical tips: 1) Carry an emergency plan and medical ID if you have prior attacks. 2) For allergic angioedema, carry an epipen and know how to use it. 3) Avoid known triggers — some foods, NSAIDs, or certain procedures can set off attacks. 4) Tell dentists and surgeons if you have HAE — procedures in the mouth or throat can trigger severe swelling and need pre-treatment.

Talk with an allergist or immunologist if you’ve had unexplained swelling. They’ll help pin down the cause and set up a clear plan for treatment and prevention that fits your life. Quick action saves airway and peace of mind.