Notes

Angioedema is the rapid edema, or swelling, of the area beneath the skin or mucosa. It is normally an allergic reaction, but it can also be hereditary.

The swelling happens because of an accumulation of fluid. It tends to affect areas with loose areas of tissue, especially the face and throat, as well as the limbs and genitals.

The condition may be mild, but if it progresses rapidly, or if it affects the throat, it can cause asphyxiation. This is a medical emergency.

Angioedema is similar to urticaria, or hives. However, urticaria affects only the upper dermis, or top layer of skin. Angioedema affects the deeper layers, including the dermis, subcutaneous tissue, the mucosa, and submucosal tissues.

It is not uncommon to have both urticaria and angioedema at the same time. Signs and symptoms
The swelling deep inside the skin can affect the patient's hands, genitals, feet, the lining of the throat and bowel, and the face.

[swollen eyelid angioedema]
The swelling can affect loose folds of skin.
Signs and symptoms tend to appear suddenly and rapidly. They may remain for up to 3 days. If urticaria develops, it may be itchy.

In some cases, the swollen areas may feel hot and possibly painful.

Vision may also be affected.

Bronchospasm may occur if the lining of the throat and airways are affected. There may be breathing problems.

In severe cases, anaphylactic shock may occur, and this can be life-threatening.

Emergency medical treatment will be necessary if the person:

Suddenly develops symptoms of angioedema, like with an allergic reaction
Has breathing problems that are sudden or are worsening
Feels faint or dizzy, or if they faint or collapse
If the person knows they have an allergy, they may have an autoinjector, such as an EpiPen. They can use this while waiting for medical help.

Treatment
The treatment for angioedema depends on the cause, but the most important action is to ensure a free airway. This means that in an emergency, a breathing tube might be placed for safety.

An allergic reaction may be treated with epinephrine, which is the drug in an EpiPen. Other medications include antihistamines and corticosteroids.

If the cause is hereditary, the patient may receive a concentrate of the the C1 inhibitor, the protein they are missing, and fresh frozen plasma.

Where appropriate, identifying and avoiding the allergen that leads to angioedema is key to preventing the occurrence of this condition.