What causes allergic tonsillitis?which are specific allergens?

Allergy: This is the body's reaction to materials it finds a necessity to eliminate. When you breathe in an allergen the reaction with antibodies creates an inflammatory response. The allergens may differ from person to person and that is why detailed testing by an allergist physician is necessary.

Tonsils not allergic: Tonsillar tissue is lymphatic in origin and function covered by mucosa. As such the mucosal lining could swell with any acute allergic reaction involving the mouth. However, I am unaware of any allergic reaction that would cause isolated acute tonsillar inflammation (tonsilliitis).