Basel standards:
- Acute urticaria, localised, without mucosal involvement and angioedema:
- Antihistamines (off-label up to 4 times the dose possible, often done and even stated in the guidelines for chronic urticaria)
- H1 blockers
- First choice: Levocetirizine (Xyzal®) p.o. 5 mg 1x tgl
- Alternative: desloratadine (Aerius®) p.o. 5 mg 1x tgl.
- Alternative: Fexofenadine (Telfast®) p.o. 180 mg 1x tgl.
- Generalised form without mucosal involvement:
- In acute relapse
- First-line antihistamines i.v. Dimetinden 1-2 x /day 1 amp. i.v., alternative Clemastine 2-4 mg i.v.
- Later switch to oral non-sedating antihistamine (see above).
- Prednisolone 50-100mg i.v. (oral steroids also possible, works more slowly), then slowly reduce dose according to clinic. If still necessary, switch from i.v. to oral steroids or discontinue steroids altogether if possible.
- In case of concurrent angioedema and mucosal involvement:
- Volume substitution
- High-dose steroids, e.g. prednisolone 250-500mg i.v., then reduce dose and switch to oral therapy
- Additional antihistamines, first i.v., then oral.
- Laryngeal glottic oedema:
- Additional adrenaline s.c. (or dilute epinephrine solution slowly i.v.) (follow local guidelines, dosages and preparations)
Note: the term 3rd generation antistamines originated as a marketing term. Levocetirizine is the enantiomer of cetirizine, desloratadine of loratadine, fexofenadine of terfenadine.
From transition to chronic urticaria, follow the therapeutic guidelines of the same (incl. 4-dose antihistamine, cyclosporine and omalizumab).