Will a throat culture be accurate if i'm on antibiotics (biaxin) for a sinus infection? have white spots on tonsils now and had a post strep issue b4

Maybe: If the strep A were resistant to Biaxin it might culture positive. It is doubtful you would acquire strep while under abx treatment. The postnasal drainage from sinusitis can cause throat irritation. A better test to see if there were any strep around would be a rapid strep that relies on the strep DNA. This would be positive if dead or alive. Likely just a virus or drainage.