Chronic Spontaneous Urticaria (CSU)

- Reassure and educate patient when possible

o There is no cure, but symptoms can be managed [3]

o Dietary restrictions often not beneficial [2]

o CSU is rarely a sign of underlying disease; when one is present, there are usually

obvious systemic symptoms

o CSU is not an allergic reaction and risk of anaphylaxis and airway compromise

with urticaria and/or angioedema is low [25]

▪ Review signs/symptoms of systemic reaction that warrant further

evaluation

- Avoid triggers:

o Mitigate stress; mental health referral if indicated

o Individualize recommendations based on triggers: NSAID, alcohol,

environmental control (especially if comorbid inducible urticaria), opioids,

infections, menstruation

▪ NSAID-exacerbated: most tolerate selective COX-2 inhibitors [3]; may

consider oral challenge if history is concerning

▪ Consider progesterone/catamenial dermatoses if hives only occur

(peri)menstrually or lesions not clearly urticarial

▪ ACEI most common cause of drug-induced angioedema; consider

angiotensin II receptor blockers, dipeptidyl peptidase IV inhibitors

(gliptins) and neprilysin inhibitors [1]• Can onset at any time after starting ACEI and may continue for up to 6 months after cessation [26]

- Treatment of Helicobacter pylori infection should be individualized, with careful consideration of risks vs benefits and patient preferences, as there is very low-grade evidence regarding H pylori eradication improving CSU outcomes [2, 3, 16]

- Treat any identify parasitic infections (patients born in or traveled to endemic areas)

- Treat comorbid rheumatologic disease

- Pseudoallergen and low-histamine diets have little evidence for efficacy, but may consider 3- 4 week trial based on patient preference [1]

- Monitoring disease activity at every visit

o Utilize disease activity, control and QOL scales per above

- Escalate therapy at 2-4 week intervals, see below

- CSU is not a risk for allergic reactions to COVID vaccination [27]

- Pregnancy: 51.1% of patients improve, 28.9% worsen and 20% have no change in CSU

during pregnancy

o Post-partum, 43.8% had similar disease activity compared to that during

pregnancy [28]