Usage of antibiotics right after one course of different antibiotic ends.

Dear Ask The Doctor: Hello, I have an upper respiratory tract infection and my doctor prescribed me NOVIDAT ( ciprofloxacin ) which is not really helping the problem. i checked on the internet and found out its not really meant to be prescribed for upper respiratory tract infections. I wanted to know can i start another course of an antibiotic as soon as the 5 days course of Novidat completes ? i've been prescribed erythromycin from another doctor but i just want to be sure if i can immediately start another course or should i wait for some days and then start the RIGHT treatment ? Please assist me .. i'll be really greatful ! Thank you, Best Regards, Farhan.

Dear Farhan: Unless you have an allergy to erythromycin or liver disease, it is safe to take erythromycin. If your current treatment with ciprofloxacin is not benefiting you, I would advise that you switch to erythromycin without having to complete the entire course of the drug.