“How long does it take for a sinus infection to go away with antibiotics?”

7-10 days

That is a loaded question. "Sinus" is probably the most commonly misused word in medicine. The GREAT majority of upper respiratory illnesses diagnosed as "sinus infections" are actually simple colds, which are caused by rhinoVIRUSES and DO NOT RESPOND TO ANTIBIOTCS. That's right, a common cold. But primary care personnel (FP's, NP's, and PA's) most commonly avoid telling the patient that he/she has a cold, simply because patients hate to hear it, because they know there is no cure other than the passage of time (1 to 2 weeks). By calling it a "sinus infection" and prescribing antibiotics, it most likely ensures that the next time you get a "sinus infection," you will seek care with them again. So you leave their office happy, relieved, and grateful that you have been diagnosed accurately and have been given effective treatment. In addition to those good effects, the caretaker avoids having to explain the difference between viral and bacterial illnesses, why your illness won't respond to any medication, and having you leave unsatisfied with the service and saying to yourself that it was a wasted trip and vowing not to return when it happens again. The antibiotics (and whatever other "decongestants" or cough medicines) that were prescribed have NO BENEFICIAL EFFECT WHATEVER, but may have side effects of drowsiness or rapid heart rate. Your symptoms resolve about the time you're finishing the antibiotics, which makes you think the antibiotics cured you. NOT SO. When antibiotics work, they work (create a dramatic improvement) within 48 hours of being taken. If that doesn't happen, it confirms that the illness is viral, and that the only thing that will help is the passage of time, usually one to two weeks. The cough, however, can last up to 3 months, gradually improving over that period of time. While technically the common cold does produce a sinus infection, it is a VIRAL infection, not bacterial, and antibiotics have NO EFFECT on viral illnesses. When you have a cold, you also have rhinitis, pharyngitis, and usually bronchitis. These are all of the areas that are infected by the virus, so the more appropriate summary diagnosis is "viral upper respiratory infection" (or in medical lingo, a URI), which is a longer name for the common cold. There are at any one time about 140 rhinoviruses in circulation, and they mutate, so it is unlikely a vaccine will be developed. If you have muscle aches and profound fatigue in association with the usual cold symptoms, you may have influenza or COVID. In that case, a COVID test should be done, and if it is positive, Paxlovid should be taken. It is a very effective treatment for COVID but does not work for influenza or the common cold. Hope this helps.

10 days