Severe Allergic Reaction (Anaphylactic Shock) (cont.)
What Are Signs and Symptoms of a Severe Allergic Reaction?
The symptoms of anaphylaxis can vary. In some people, the reaction begins very slowly, but in most the symptoms appear rapidly and abruptly.
- The most severe and life-threatening symptoms are difficulty breathing and loss of consciousness.
- Difficulty breathing is due to swelling and/or spasm in the airways (which can include swelling of the tongue or the large and small parts of the airways). In very rare cases, breathing can stop altogether.
- Loss of consciousness is due to dangerously low blood pressure, which is called "shock."
- In the most serious cases, the heart can stop pumping altogether.
- These events can lead to death from anaphylaxis.
- While some symptoms are life threatening, others are merely uncomfortable. Generally, a reaction must involve at least two different body systems, such as skin and heart, to be considered anaphylaxis.
- Skin: Most anaphylactic reactions involve the skin.
- Hives (urticaria, welts, or wheals [raised bumps]): Hives can cause severe itching
- Generalized erythema (redness)
- Swelling in the face, eyelids, lips, tongue, throat, hands, and feet
- Breathing: Swelling of the surrounding tissues narrows the airways.
- Difficulty breathing, wheezing, chest tightness
- Coughing, hoarseness
- Nasal congestion, sneezing
- Cardiovascular: Blood pressure may drop to dangerously low levels.
- Rapid or irregular heart beat
- Dizziness, faintness
- Loss of consciousness, collapse
Medically Reviewed by a Doctor on 10/11/2017
Jerry R. Balentine, DO, FACEP
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