I believe the burning sensation is directly related to the nicotine, not PG or VG. I would love to reopen this debate. I have been experiencing it and has been steadily getting worse. I tried 8mg liquid for a day or so (at the same consumption rate) and the soreness subsided, but at the expense of nicotine withdrawal symptoms. I am back to the higher (18mg) nicotine and the soreness has returned. It is worse at night and after I have just eating something. The burning sensation is on the flat top surface and sides of the tongue. No visual anomalies, only the sensation. B complex has had no effect, but makes
sense since nicotine reduces several B vitamins in the body. The recommendation on this board to apply olive oil brings relief (I am currently testing to see if regular application causes perm reduction in the sensation).