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Anaphylaxis

• Overview
• Symptoms
• Treatment
• Prevention

Alternative Names:

Anaphylactic reaction; Anaphylactic shock; Shock - anaphylactic

Symptoms:

Symptoms develop rapidly, often within seconds or minutes. They may include the following:

• Difficulty breathing
• Wheezing
• Abnormal (high-pitched) breathing sounds
• Confusion
• Slurred speech
• Rapid or weak pulse
• Blueness of the skin ( cyanosis ), including the lips or nail beds
• Fainting , light-headedness , dizziness
• Hives and generalized itching
• Anxiety
• Sensation of feeling the heart beat ( palpitations )
• Nausea, vomiting
• Diarrhea
• Abdominal pain or cramping
• Skin redness
• Nasal congestion
• Cough

Signs and tests:

Examination of the skin may show hives and swelling of the eyes or face. The skin may be blue from lack of oxygen or may be pale from shock. Angioedema in the throat may be severe enough to block the airway.

Listening to the lungs with a stethoscope may reveal wheezing or indicate fluid (pulmonary edema). The pulse is rapid, and blood pressure may be low. Weakness, pale skin, heart arrhythmias, mental confusion, and other signs may indicate shock.

Testing for the specific allergen that caused anaphylaxis (if the cause is not obvious) is postponed until after treatment.

References:

The diagnosis and management of anaphylaxis: an updated practice parameter. J Allergy Clin Immunol . 2005 Mar;115(3 Suppl):S483-523.

• Review Date: 5/3/2006
• Reviewed By: David A. Kaufman, M.D., Assistant Professor, Division of Pulmonary, Critical Care & Sleep Medicine, Mount Sinai School of Medicine, New York, NY. Review provided by VeriMed Healthcare Network.

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