What phases of the allergic response are blocked by intranasal corticosteroids?

Intranasal corticosteroids are effective in managing allergic rhinitis and work by targeting both the early-phase and late-phase responses of the allergic reaction.

In the early phase of an allergic response, allergens trigger the immediate release of mediators such as histamine, leading to symptoms such as sneezing, nasal congestion, and itching. Corticosteroids help by reducing inflammation, preventing the recruitment of immune cells, and decreasing the overall hyperreactivity of the nasal mucosa.

The late-phase response occurs hours after the initial exposure and is characterized by a more sustained inflammatory reaction, involving the recruitment of additional immune cells, such as eosinophils and T lymphocytes. Intranasal corticosteroids effectively limit this response by modulating the expression of various inflammatory mediators and maintaining a lower level of inflammation.

By acting on both phases, intranasal corticosteroids provide comprehensive relief from the symptoms of allergic rhinitis, making them a cornerstone in the treatment of allergic conditions.