1. Anaphylaxis, Acute
Allergic Reactions, and
Angioedema

2. ANAPHYLAXIS AND
ALLERGIC REACTIONS

5. Clinical Features
Majority: signs and symptoms begin suddenly,
often within 60 minutes of exposure
biphasic phenomenon
 3-20% of patients
 caused by a second phase of mediator release,
peaking 4-8 hours after the initial exposure and
exhibiting itself clinically 3-4 hours after the initial
clinical manifestations have cleared
late-phase allergic reaction
 primarily mediated by the release of newly generated
cysteinyl leukotrienes, the former slow-reacting
substance of anaphylaxis

6. Diagnosis
Serum tryptase levels

8. Treatment

9. Treatment

10. Treatment

11. Disposition and Follow-Up
Admission/Discharge
Admission to hospital is rare
All unstable patients with anaphylaxis refractory
to treatment or where airway interventions were
required should be admitted to the intensive
care unit.
Patients who receive epinephrine should be
observed in the ED, but the duration of
observation is based on experience rather than
clear evidence.

12. Disposition and Follow-Up
Admission/Discharge
If patients remain symptom free after
appropriate treatment following 4 hours of
observation, the patient can be safely
discharged home.
prolonged observation periods should be
considered in patients with a past history of
severe reaction and those using -blockers

13. Disposition and Follow-Up

14. URTICARIA AND
ANGIOEDEMA

15. Urticaria
Treatment of urticarial reactions is generally
supportive and symptomatic, with attempts to
identify and remove the offending agent.
Antihistamines, with or without corticosteroids,
are usually sufficient, although epinephrine can
be considered in severe or refractory cases.
The addition of a histamine-2 receptor blocker,
such as ranitidine, may also be useful in more
severe, chronic, or unresponsive cases.

16. Angioedema
Angioedema of the tongue, lips, and face has
the potential for airway obstruction.
Management is supportive, with special
attention to the airway, which can become
occluded rapidly and unpredictably.
Epinephrine, antihistamines, and steroids are
often still used, but benefits have not been
clearly demonstrated.

17. Angioedema
Patients with mild swelling and no evidence of
airway obstruction can be observed in the ED
and discharged if swelling diminishes.
Patients with moderate to severe swelling,
dysphagia, or respiratory distress are best
admitted for close observation.

18. Take home message

19. ANY QUESTION?