Since your whole family is suffering these strange symptoms you're probably on the right track that the problem is environmental. Either mold/fungus in the house or maybe environmental problems with pollution, radiation, etc in your town/neighborhood.
Colloidal Silver is always worth trying since it knocks out a broad range of infections and the well made stuff has almost zero possibility of complication (it's 99.99% water with trace amounts of silver).
If the store bought stuff seems to work, get an inexpensive CS makers (under $100) and make your own for pennies.