most sinus infections are viral and do not require any antibiotics. for the few that are bacterial amoxillin at an appropriate dose or an appropriate length of time would be one of the antibiotic choices. if you are self-diagnosing and self-treating with an old prescription or someone else's prescription i would not recommend that you do this.
is amoxicillin appropriate for a sinus type infection/sore gland when swollowing? . will amoxicillin help for sinus infection? . .