Spontaneous urticaria (hive/welts) and angioedema (swelling) is caused by a random release of histamine from unstable mast cells. It is not caused by an allergy to a food/drug/other. Some patients have chronic symptoms occurring daily/most days for 6 weeks called chronic spontaneous urticaria (CSU). The diagnosis is based on the pattern of your symptoms, and exclusion of other causes of hives and swelling. Some patients present with swelling only. Treatments are aimed at stabilising mast cells to stop/reduce frequency and severity of symptoms. In the first instance this is long acting, non sedating antihistamines taken up to four times per day which you can titrate yourself. You can read more about his condition here Chronic Spontaneous Urticaria Leaflet | Allergy UK | National Charity If this fails to improve symptoms and you continue to have frequent episodes of urticaria and/or angioedema the next step in the treatment ladder is Omalizumab.
Resolution of spontaneous urticaria and angioedema is often seen, so antihistamines/omalizumab can be weaned to stop, if symptoms permit.
See our information leaflet which has been designed in collaboration with a patient to help you mage your symptoms of CSU.