Depends, mild and most sinus infections can go away on it own. If you have a lot of runny nose, post-nasal drip try allergies medications. If you feel it is not drainage but pressure, then drinking water, hot steam showers, inhalating steam can help.

Severe sinus infections that won't go away after 2 weeks may need antibiotics

IS IT ACTUALLY AN INFECTION? If so, that PROBLEM should be EVALUATED with proper testing to determine the exact cause and treated appropriately.

The vast majority of cases of acute sinus infection is due to viral infection, resolves spontaneously and does not require any antibiotics. Only 0.5-2% of cases result in secondary bacterial infection requiring antibiotics.