HI, thanks for using healthcare magic
Symtoms of sinus disease can occur most commonly as a result of allergies, viral or bacterial infection.
In the case of a bacterial infection, like your husband is experiencing, antibiotics are needed as part of the therapy. Normally when
amoxicillin is used for
sinus infection , it is taken 3 times a day. IF he is using twice daily , it would not be as effective.
In severe cases or where is a slow response the antibiotics have to be taken for an extended period of time (up to 3 or 4 weeks).
He may want to consider speaking to the doctor regarding the
dosing interval of the amoxicillin or changing to another antibiotic that may help him.
In terms of the
flu, it can cause severe symptoms. The main aspect of treatment in most persons is rest,fluids and the use of medication to treat any symptoms (as he is already doing)
I hope this helps