Anaphylaxis is an acute systemic (whole body) type of allergic
reaction which occurs when a person has become sensitized to a
certain substance or allergen and is again exposed to the allergen.
Some drugs, such as those used for pain relief or for X-rays, may
cause an anaphylactoid reaction on first exposure. Histamines and
other substances released into the bloodstream cause blood vessels
to dilate and tissues to swell. Anaphylaxis may be life-threatening
if obstruction of the airway occurs, if blood pressure drops, or if
heart arrhythmias occur.
Review Date: 06/29/2010
Reviewed By: Paula J. Busse, MD, Assistant Professor of Medicine, Division of
Clinical Immunology, Mount Sinai School of Medicine, New York, NY.
Review provided by VeriMed Healthcare Network. Also reviewed by
David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)
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