Sites vary, but most mention a median range of between 30-40% humidity.
During extremely cold weather, your home loses humidity to the
outdoors and may drop as low as 5%. By comparison, typical humidity in
the Sahara Desert is about 25%! Generally, one does not want to have a
home humidity any lower than 30%. Optimal comfort is ...
Typically itchy throats are associated with post nasal drip, dry air, allergies, or some other irritant.
If it's allergen related, an antihistamine (Benadryl, Zyrtec, Claritin, etc) can be helpful. If you're developing some sort of virus or bacterial infection, often a warm salt water gargle helps to alleviate discomfort and can prevent a full-on infection....