Well with upper respiratory infections, strep throat, pneumonia and whooping cough do need antibiotics because they are bacterial. But most bronchitis, a lot of sinus infections and sore throats are viral and an antibiotic won't do them any good. But studies have shown that these are viral and even giving them an antibiotic won't shorten them. Sinus infections are particularly difficult because there isn't a test to tell if it is viral or bacterial. If it starts getting better by then that's probably a virus.
Viruses get better quicker than bacterial infections.
If it is not better by seven to ten days, go see your doctor, because it probably is a bacterial infection. The group recommends medications like cough suppressants and decongestants that will treat the symptoms. They won't make you better by making the disease go away, but they will make it easier to wait it out. Most viral infections get better on their own. Doctors are going to have to help educate their patients that antibiotics don't work on viruses, and that antibiotic resistance is a big problem and everybody needs to work together.