Chronic urticaria has a very well described stepwise treatment standard, which I will describe briefly here. If resolution is not achieved with the method described in one step, the next step is executed.
- A second generation H1 antihistamine like cetirizine is begun with standard daily dosing. Triggers should be avoided wherever possible.
- Dosage of second generation H1 antihistamine is increased.
- Another second generation H1 antihistamine is added to the regimen. (For example, cetirizine and fexofenadine taken together).
- An H2 antihistamine is added. About 15% of histamine receptors in the skin are H2, so some patients see benefit from this.
- A leukotriene receptor antagonist like montelukast is added.
- A first generation H1 antihistamine like diphenhydramine is added at bedtime.
- A strong antihistamine like hydroxyzine or doxepin is added and dosages increased accordingly.
- If all else has failed, consider addition of medications like Xolair, cyclosporine, or other immunosuppressants.
Treatment of angioedema is dependent upon the cause of the angioedema (C1 esterase deficiency, ACE inhibitor, etc). However, it is generally agreed upon that upper airway swelling, even if mild, should be treated aggressively. Intramuscular epinephrine is indicated for this situation, with advisories in numerous papers to administer epinephrine as early as possible if airway swelling is present.
Reactions caused by IgE are the most likely to respond immediately to epinephrine. Hereditary and acquired angioedema are less likely to respond to epinephrine. If the patient is on beta blockers, glucagon is the drug of choice, as beta blockers interfere with action of epinephrine.
I am doing a detailed follow up post on treatment options for the various types of angioedema.
References:
Jonathan A. Bernstein, et al. The diagnosis and management of acute and chronic urticaria: 2014 update. J Allergy Clin Immunol Volume 133, Number 5.
Zuberbier T, Maurer M. Urticaria: current opinions about etiology, diagnosis and therapy. Acta Derm Venereol 2007;87:196-205.
Ferdman, Ronald M. Urticaria and angioedema. Clin Ped Emerg Med 2007; 8:72-80.