What is most effective treatment for nasal polyps and maxillary sinusitis?

Antibiotics & sprays: Antibiotics help the infection .Nasal steroid sprays and irrigation control of major allergies and sometimes steroids by mouth sinus surgery some times is needed.

A good specialist: Nasal polyps and sinusitis can be treated but each treatment should be tailored to the individual. Some patients respond better than others. Generally the treatment will entail a combination of different medicines (antibiotics and/or steroids - oral or nasal). I would consult a good ENT or allergist.