I have a question - my husband has been on pomalyst/dara for 1 yr now...and it seems he always gets sinus infections....he's had 5 sinus infections within the last year....I know the drug effects the respiratory....is this just going to be on going...we always seem to have to get a zpak from the dr. .....should we be increasing our Vitamin C or is this just typical....my husband has always been prone to getting a sinus infection even before he had myeloma....any comments