It’s one of the most common—and most frustrating—complaints in the Emergency Department: the patient covered head-to-toe in hives, miserable, itching, and desperate for relief. In this episode of EM Pulse, we welcome back ED Clinical Pharmacist Haley Burhans to tackle the “uncomfortable” topic of urticaria. We move past the myths of one-and-done doses and explore why your standard allergy dosing might be leaving your patients itching for more.

The Power of Second-Generation Antihistamines

Haley explains why second-generation antihistamines (cetirizine, levocetirizine, fexofenadine) should be your first-line ED therapy, rather than the old school standard, diphenhydramine (Benadryl).

Xyzal vs. Zyrtec: We break down the L-enantiomer (levocetirizine) and whether it actually beats its predecessor in preventing drowsiness.
The “Double Dose” Pearl: For acute urticaria in the ED, 10mg of cetirizine isn’t enough. Haley recommends starting with 20mg for adults (or doubling the weight-based dose for kids) to see relief within 20–60 minutes.
The 4x Rule: Guidelines now support up to four times the standard daily dose for refractory cases (usually split BID). We discuss the safety data behind these higher regimens and why they are tolerated so well.

The Steroid Trap and the Rebound Effect

Patients often come in requesting steroids but they are NOT the primary cure for urticaria.

The Antihistamine Backbone: Steroids treat inflammation, but the antihistamine treats the underlying stimulus. If a patient stops their antihistamines and only takes a steroid burst, they are set up for a miserable rebound.
Dosing Strategies: If you do use steroids, keep it to a burst or taper of 10 days or less. We discuss the utility of methylprednisolone (Medrol Dosepak) versus a simple prednisone burst/taper or a course of longer-acting dexamethasone.

Beyond the Basics: Benadryl and the MABs

The Danger of “Dirty” Drugs: Why diphenhydramine has fallen out of favor due to its sodium channel blocking side effects, anticholinergic toxicity, and psychiatric risks.
The Future of Itch: A look at emerging biologics like omalizumab. While these IgE-blockers shouldn’t be started in the ED, it’s important to know about them to treat patients who are taking them, or who present with rebound urticaria after recently stopping them.

Key Takeaways

Go Big on Second Generation Antihistamines: Start with a double dose of cetirizine in the ED. It’s safe, effective, and less sedating than first-generation alternatives. Discharge patients on that double dose twice a day.
Think Long-Term: Urticaria pathways need time to “cool down.” Advise patients to stay on the prescribed meds/doses for 1–2 months, not 1–2 days.
Steroids are Adjuncts: Use a short burst (<10 days) for severe distress, but never as monotherapy.
The Taper is Key: Encourage a slow taper of medications to prevent symptom recurrence.
Managing Expectations: Most urticaria has no identifiable cause (often viral or idiopathic). Reassure the patient that while we may not find the why, we can help manage the itch.

How do you handle the “itch that won’t quit”? Do you have a favorite antihistamine cocktail? Share your experience with us on social media @empulsepodcast or at ucdavisem.com

Hosts:

Dr. Julia Magaña, Professor of Pediatric Emergency Medicine at UC Davis

Dr. Sarah Medeiros, Professor of Emergency Medicine at UC Davis

Guests:

Haley Burhans, PharmD, Emergency Medicine Clinical Pharmacist at UC Davis

Resources:

The international EAACI/ GA²LEN/ EuroGuiDerm/ APAAACI guideline for the definition, classification, diagnosis, and management of urticaria

Emergency Department and Primary Care Clinical Pathway for Evaluation/Treatment of Children with Urticaria or Angioedema (CHOP)

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Thank you to the UC Davis Department of Emergency Medicine for supporting this podcast and to Orlando Magaña at OM Productions for audio production services.