#Urticaria (Hives), Chronic
Chronic = it is recurrent, with signs and symptoms recurring most days of the week, for six weeks or longer.
References
Am Fam Physician. 2017 Jun 1;95(11):717-724. http://www.aafp.org/afp/2013/0501/p626.html
Am Fam Physician. 2011 May 1;83(9):1078-1084. http://www.aafp.org/afp/2011/0501/p1078.html