Hi Dear, Understanding your concern. Oral thrush in infant seems to be due to fungal infection and poor oral hygiene which sometimes occurs after intake of heavy antibiotics and remains persistent and leading to formation of thick white layer in oral cavity and its surfaces. I would suggest you to - Maintain complete oral hygiene. - Give Probiotics like Yoghurt in diet and Amphotericin B as antifungal suspension. -Avoid sharp, hot and spicy foods. - Swish with nystatin suspensions. You should visit oral pathologist once if symptoms keeps on persisting and start treatment after prescription. Go for biopsy of lesions if symptoms keeps on persisting. Best Wishes, Harry Maheshwari