Urticariahttps://en.wikipedia.org/wiki/Hives
Urticaria is a kind of skin rash with red, raised, itchy bumps. Often the patches of rash move around. Typically they last a few days and do not leave any long-lasting skin changes. Fewer than 5% of cases last for more than six weeks. Urticaria frequently occur following an infection or as a result of an allergic reaction such as to medication or food.

Prevention is by avoiding whatever it is that causes the condition. Treatment is typically with antihistamines such as diphenhydramine and ranitidine. In severe cases, corticosteroids or leukotriene inhibitors may also be used. Keeping the environmental temperature cool is also useful temporarily. For cases that last more than six weeks immunosuppressants such as ciclosporin may be used.

It is a common disease as about 20% of people are affected. Cases of acute urticaria occur equally in males and females while cases of long duration are more common in females. Cases of acute urticaria are more common among children while cases of long duration are more common among those who are middle aged. If it lasts more than 2 months, it often lasts for years and then goes away.

○ Treatment ― OTC Drugs
Acute urticaria usually resolve within a week, but chronic urticaria can last for years although most of them go away at some point. In the case of chronic urticaria, it is recommended to take antihistamine on a regular basis and wait for it to go away on its own.

OTC antihitamines. Cetirizine or levocetirizine are more effective than fexofenadine but make you drowsy.
#Cetirizine [Zytec]
#LevoCetirizine [Xyzal]

For chronic urticaria, non-drowsy antihistamines such as fexofenadine are preferred.
#Fexofenadine [Allegra]
#Diphenhydramine [Benadryl]
#Loratadine [Claritin]
  • Lesions suspected of being Erythema multiforme minor or urticarial vasculitis rather than typical urticaria.
  • It is a typical case of hives. Lesions can move every few hours.
  • Urticaria ― arm
  • Cold urticaria
  • Cold urticaria
  • Hives on the left chest wall. Notice that the lesions are slightly raised.
  • Typical urticaria
  • Urticarial Vasculitis
  • Dermographic urticaria; It is usually a chronic urticaria and can persist for several years before suddenly disappearing.
  • Dermatographic urticaria
References Acute and Chronic Urticaria: Evaluation and Treatment 28671445
Urticaria, often characterized by itchy wheals and sometimes swelling of the deeper skin layers, is typically managed by avoiding triggers, if known. The primary treatment involves second-generation H1 antihistamines, which can be adjusted to higher doses if needed. Additionally, other medications like first-generation H1 antihistamines, H2 antihistamines, leukotriene receptor antagonists, potent antihistamines, and short courses of corticosteroids may be used alongside. For persistent cases, referral to specialists for alternative therapies like omalizumab or cyclosporine may be considered.
 Urticaria and Angioedema: an Update on Classification and Pathogenesis 28748365
 Chronic Urticaria 32310370 
NIH
Second-generation H1-antihistamines (e.g., cetirizine, loratadine, fexofenadine), Omalizumab, Ciclosporin, and short courses only of systemic corticosteroids
 Angioedema 30860724 
NIH
Angioedema is non-pitting edema that involves subcutaneous and/or submucosal layers of tissue that affects the face, lips, neck, and extremities, oral cavity, larynx, and/or gut. It becomes life-threatening when it involves the larynx.