Anaphylaxis, or anaphylactic shock, is a severe allergic reaction. Common allergens are penicillin and bee/wasp venom.
Mediators (i.e., histamine, leukotrienes, prostaglandins) are released from mast cells. Flushing and an itchy skin, a red rash (urticaria), shortness of breath and hypotension are present.
Sometimes swelling of the tongue, pharynx and larynx (laryngeal edema) and wheezing (bronchospasm) occur.
1. Immediate intravenous normal saline is begun to raise the blood pressure;
2. High flow oxygen by mask is monitored by pulse oximetry;
3. Epinephrine 0.4 cc subq (peds: 0.01 cc/kg) (1:1000), or for severe shock 1 to 10 cc (1:10,000) slow IV push;
4. An antihistamine such as diphenhydramine 50 mg IV (peds: 1 mg/kg) is given;
5. Methylprednisolone 125 mg IV (peds: 1 mg/kg)is administered;
6. A histamine receptor blocker such as ranitidine 50 mg IV (peds: 0.5 mg/kg) is given over 5 min, and
7. A nebulized beta-agonist (i.e., albuterol) is administered for bronchospasm.