Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain swollen papillae at the back of tongue seems to be swollen Circumvallate papillae and can occur due to a number of common causes like Allergic reaction to any medicine or food, eating very hot foods,burning with chemicals like concentrated solution of mouthwash, post nasal drip, sinusitis, throat infection,acid reflux etc.. You should consult an Oral Physician and get evaluated and a thorough clinical evaluation can help in confirmation of the cause and treatment can be planned accordingly.. As of now you can do warm saline gargles, soda bicarb gargles and take anti-inflammatory medicine like Ibuprofen.. Hope this information helps.. Thanks and regards. Dr. Honey Nandwani Arora.