Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain seems that you had an upper respiratory tract infection along with sinusitis leading to congestion and other symptoms and after taking mucolytics like [Mucinex] it has resolved and now there is still infection in sinuses which will be resolved gradually.. As of now to relieve sinus congestion you can take a short course of antibiotics like Augmentin or Azithromycin for 5 days. Continue taking Ibuprofen. Do steam inhalations and use a cool mist humidifier in your room. Saline nasal sprays will help.. The next part of your question is white coating on tongue. The most common cause of white coating on tongue is oral thrush which is a fungal infection and for this consult an Oral Physician and get evaluated and once thrush is confirmed he/she can advise you to take anti-fungal agents like Nystatin mouthwash and Clotimazole lozenges. Take more of probiotics like Yoghurt and garlic. Drink plenty of water to prevent dry mouth.. Hope this information helps.. Thanks and regards. Dr.Honey Nandwani Arora.