When a bee stings it injects:-
Formic acid
Bee stings contain formic acid. Chemically, it is HCOOH. Formic acid is also found in stinging leaves and the bites and stings of other insects which can be neutralized by applying a basic calamine solution or baking soda solution or slaked lime.
Moreover, wasp stings are basic in nature which can be neutralized by applying vinegar or lemon juice which are acidic in nature.