Welcome to health care magic forum.
Itchy tongue as well as throat may occur due to-intake of allergic foods,vitamin deficiency
,intake of spicy foods.
I would advice you to maintain oral care well.
Gargle frequently with lukewarm saline.
Avoid spicy foods,tobacco or pan chewing.
Plenty of fluids as well as nutritious diet has to be administered.
Usually in such cases,corticosteroids
as well as vitamin b-complex supplements has to be administered.
Hope this helps.