This week I am discussing chronic spontaneous urticaria (CSU) better known as hives, which is a common skin condition affecting up to 1% of the general population. Chronic urticaria affects women more often than men between the ages of 20 and 40, although an individual can develop hives at any age. It causes significant physical, psychological and economic burdens, with healthcare costs in the U.S estimated to exceed $200 million per year. This itchy skin condition is caused when mast cells in the skin are activated and release a host of bioactive mediators, including histamine that causes raised welts and redness and itching over different parts of the body. When hives persist for longer than 6 weeks, they are considered chronic. Up to 40% of patients may also have associated soft tissue swelling called “angioedema.” Many hive patients are very frustrated with this very annoying condition and make associations with food or other potential triggers causing their hives. However, when hives are chronic, seldom is food allergy the underlying cause and having hay fever (allergies) is also not a cause of hives. In fact, for most cases of CSU, an underlying cause is never found. An exception would be patients who have hives caused by physical stimuli like scratching and cold or hot temperatures as well as several other physical triggers, now referred to as chronic inducible urticaria.
Current management strategies for hives recommend a stepwise approach, which begins with increasing doses of second-generation non-sedating antihistamines like Fexofenadine (Allegra™), Cetirizine (Zyrtec™), Levocetirizine (Xyzal) ™ or Loratadine (Claritin™), which are inexpensive and over the counter in pharmacies. As only approximately 40–50% of CSU patients respond to H1-antihistamines, treatment with more advanced therapies now approved by the FDA for CSU may be necessary. These medications include biologics such as omalizumab (Xolair™) and more recently dupilumab (Dupixent™) and a newly approved small molecule called remibrutinib (Rhapsido™). All of these medications have been shown to be effective in controlling hives in patients unresponsive to H1-antihistamines but there are nuances on who may respond best to one of these treatments or another. Choosing the right medication should be determined by your treating physician taking into account patient personal preferences and values as all these medications have potential side effects. To help disseminate education and knowledge about hives, the Urticaria Center of Reference and Excellence (UCARE.org) has been established to identify and certify centers of excellence worldwide in the management of hives. There are now seven such referral centers in the US, all actively engaged in advanced patient care, clinical and translational research and education pertaining to urticaria and angioedema. They are charged with helping healthcare communities provide excellent care that improves the quality of life for urticaria patients. So, the bottom line is if you or a loved one has hives, don’t despair. There are now excellent approaches for managing this annoying problem.
