Question: what is the best medicine for a severe sinus infection?
Answer: Saline nasal spray, which you spray into your nose several times a day to rinse your nasal passages.
Nasal corticosteroids. These nasal sprays help prevent and treat inflammation. ... 
Decongestants. ... 
OTC pain relievers, such as acetaminophen (Tylenol, others), ibuprofen (Advil, Motrin IB, others) or aspirin.