Anaphylaxis (Emergency Treatment)
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Emergency protocols vary by institution. Use clinical judgment and local policy.
Initial steps (adult)
- Stop the trigger (stop infusion/medication; remove offending agent if possible).
- Call for help (activate emergency response/EMS); place patient on monitor.
- Position: supine with legs elevated; in pregnancy, left uterine displacement if feasible.
- Oxygen and airway support as needed.
- Epinephrine IM promptly; repeat every 5–15 minutes for persistent symptoms.
- IV access; treat hypotension with large-volume isotonic crystalloid bolus.
- Consider nebulized albuterol for bronchospasm/wheezing.
- Give H1 antihistamine (symptom relief for urticaria/pruritus) ± H2 blocker.
- Consider corticosteroid as an adjunct (not immediate rescue; may be used for protracted/refractory cases per local protocol).
Medication quick table (dose • route • how supplied • DailyMed)
| Medication | How used (typical adult) | How supplied (examples) | DailyMed |
|---|---|---|---|
| Epinephrine (adrenaline) 1 mg/mL (1:1000) |
First-line for anaphylaxis. 0.3–0.5 mg IM (0.3–0.5 mL of 1 mg/mL) into anterolateral thigh. Repeat every 5–15 min if symptoms persist/worsen. |
Commonly as 1 mg/mL vials/ampules (single-use or multi-dose depending on product). | Adrenalin® (epinephrine) 1 mg/mL |
| Diphenhydramine H1 antihistamine |
Adjunct for urticaria/pruritus (does not treat shock/airway edema). Example: 25–50 mg IV (slow) or IM once; repeat per protocol. |
Injection commonly 50 mg/mL in vials/ampules. | Diphenhydramine injection |
| Famotidine H2 blocker |
Adjunct (often used with H1 blocker for cutaneous symptoms). Example: 20 mg IV once (institutional protocols vary). |
Injection solution (commonly supplied as vials/ampules). | Famotidine injection |
| Hydrocortisone (as sodium succinate) corticosteroid |
Adjunct (not a substitute for epinephrine; onset is delayed). Example regimens vary (e.g., 200–250 mg IV once) per protocol. |
Powder for solution for IV/IM in various vial sizes (product dependent). | Solu-Cortef® (hydrocortisone) |
| Albuterol (nebulized) β2 agonist |
For bronchospasm/wheezing after epinephrine and airway support as needed. Dose per local asthma/anaphylaxis protocol. |
Inhalation solution in unit-dose vials or bottles (varies by product/strength). | Albuterol inhalation solution |
Note: Older protocols sometimes listed ranitidine; ranitidine products were withdrawn in the U.S. in 2020 due to NDMA impurity concerns. (See FDA announcement; some markets may differ.)
References
1. Tang AW. A practical guide to anaphylaxis. Am Fam Physician. 2003;68(7):1325–1332. PMID: 14567487. :contentReference[oaicite:0]{index=0}
2. Cardona V, et al. World Allergy Organization Anaphylaxis Guidance 2020. World Allergy Organ J. 2020;13(10):100472. PMID: 33204386. :contentReference[oaicite:1]{index=1}
3. Golden DBK, et al. Anaphylaxis: A 2023 practice parameter update. Ann Allergy Asthma Immunol. 2024;132(2):124–176. PMID: 38108678. :contentReference[oaicite:2]{index=2}
4. Resuscitation Council UK. Emergency treatment of anaphylaxis guideline (May 2021). :contentReference[oaicite:3]{index=3}
5. U.S. FDA. FDA requests removal of all ranitidine products (Zantac) from the market (Apr 1, 2020). :contentReference[oaicite:4]{index=4}