Hello dear user! I have gone through your query and understood your concerns! Thank you for sharing them on healthcaremagic. Are you taking antibiotics too, for your sinus infection? If you are not taking antibiotics but methylprednisolone only, you might worsen the sinus infection and the nail fungus too. Don t continue taking methylpred pills more than 3 days because of your condition. Continue antibiotic therapy for the sinus infection, and the medication for your fungal infection of the toe. If your toe gets worse due to fungus, please stop the methylpred and talk with your doctor to adjust an appropriate cure of it. I hope this answer was helpful to you! Please kindly rate it and write a short review about your experience with me! Thank you and best regards! DR ERIOL.