Hi. Thanks for the query.. As per your complain white coating on tongue can be due to Yeast infection known as Oral Thrush. It is caused by yeast Candida Albicans.. White spots on the tip of tongue seems to be due to swollen and overgrowing to give papillae that can occur due to inflammation of the to field caused secondary to Infection.. You should consult an Oral Physician and get evaluated andi f Thrush is confirmed as diagnosis the Physician can advise you to take antifungal medicines like Fluconazole or Itraconazole orally.. Nystatin mouthwash and clotrimazole lozenges can be advised.. Taking more of probiotics like Yoghurt and Garlic will help in faster clearing of fungus.. Drink plenty of water to prevent Dry mouth that is common in Thrush.. Do warm saline gargle to reduce inflammation.. Hope this information helps.. If you have further questions you can visity profile and ask me a direct questions for a detailed discussion along with images so that I can guide you more appropriately.. Regards..