How likely is it for sinus infection w fever to go away wothout antibiotics?  

Likely. Antibiotics are usually no better than placebo in the treatment of sinusitis per a study this month (feb '12) in jama. Few, perhaps 5%, (those with symptoms longer than 10 days, worsening sx, or quite ill with high fever) will benefit from antibiotics. Otherwise try otc saline sinus rinses, decongestants, and time. For allergy patients oral anti-histamines or nasal steroid sprays can be helpful.
Agree with Dr. Weiss. Was going to suggest same jama article. I'm battling sinus infxn currently without abx based on the article. If does not improve, see doctor. Chronic sinusitis may require ENT eval, steroids, surgery. Be careful with otc sinus meds as can elevate bp. And don't use afrin (oxymetazoline) longer than 2 days or you'll never clear up.

Related Questions

Husband on amox generic for seven days for sinus infection...Took last pill 7 days ago. As of last night, has fever 103.3. Felt better after starting amox. Does he need a different type of antiobiotic? Time for er?

Typically . Typically sinus infections are treated for a minimum of ten days. If he is still having fever after 7 days then the antibiotics were not sufficient to cover his infection or the treatment was not long enough. He needs to be reevaluated. He should follow up with his primary care provider, if he is unable, an urgent care is a good choice. Good luck. Read more...

Had had sinus infection post-flu since Jan. Antibiotx not stopping it. What conservative treatments can ENT offer? Any home remedies I can try yet?

ENT can. perform sinus irrigation, or you can try on your own. But five months is a long time. It is time to get definitive treatment. It is also possible you might have developed a polyp or other physical deformity. Read more...