3.1 Drug induced urticarial rashes
Urticaria and urticarial rashes belong at least in part to cutaneous type I (IgE-mediated) drug- hypersensitivity reactions (Table 3)(Fig. 7). Other mechanisms involved are direct mast cell activation, immune complex formation/precipitation (Fig. 7) and activation of complement during serum sickness or interaction with metabolic pathways of drugs such as arachidonic acid metabolism (69 ). Urticaria or urticarial rashes in SARS-CoV-2 patients could be drug induced, induced by drugs, viral RNA or a mixture of both. Infection-associated re-activation or exacerbation of pre-existing urticaria might be possible as well.