AnaphylaxisHasan Radi Al-Shabaan

214010094

Learning Objectives• 1/ What is anaphylaxis? And what are its clinical

features?

• 2/ What is the cause of anaphylaxis? And what is its

pathophysiology?

• 3/ First-Aid management of anaphylaxis?

• 4/ Which groups of drugs are used and why?

Hypersensitivity• Exaggerated and inappropriate immune

response, resulting in tissue injury.

Types of hypersensitivity

What is Anaphylaxis• Anaphylaxis is a severe, potentially life-threatening

allergic reaction.

• It can occur within seconds or minutes of exposure

to something you're allergic to, such as the venom

from a bee sting or a peanut.

Pathophysiology

Clinical features• The most common organ systems involved include

the cutaneous, respiratory, cardiovascular, and

gastrointestinal (GI) systems.

Difficulty breathing DizzinessNausea

swelling of the tongue

Itchinghives

Causes of anaphylaxis• Foods:

• peanuts, seafood, milk

• Medications:

• penicillin, NSAIDs

• Insect stings:

• bees, wasps, ants

• Less common causes:

• Latex

• Exercise

First-Aid management of anaphylaxis

• 1. Seek emergency care

• Call for help

• 2. Inject Epinephrine Immediately

• Inject epinephrine into outer muscle of the thigh.

• 3. Do CPR if the Person Stops Breathing

groups of drugs used• Epinephrine: help maintain blood pressure,

antagonize effects of released mediators, and

prevent further release of mediators.

• Antihistamines (Diphenhydramine, Hydroxyzine):

primarily effective against cutaneous effects of

anaphylaxis.

• H2 Receptor Antagonists (Cimetidine): block effects

of released histamine at H2 receptors, thereby

treating vasodilation.

• Bronchodilators (Albuterol): These agents stimulate

beta2-adrenergic receptors in bronchial smooth

muscle, causing bronchodilation.

Summary• Definition of Anaphylaxis

• Clinical features of anaphylaxis

• Pathophysiology of anaphylaxis

• Causes of Anaphylaxis

• First-aid management

• Group of drugs used to treat anaphylaxis

References• Abbas Basic Immunology 4th edition

• http://emedicine.medscape.com