Past 5 months, bitter/metallic taste,nausea,chilitis,sore on tongue. all comes & goes frequently. no new meds. saw gp x2, dmd x1, derm x1. not reflux.

Deficiency?: It is possible that you could be deficient in Iron or Vitamin B, especially considering your medications and previous surgery. Consider discussing this possibility with your doctor and they can discuss a further evaluation and treatment plan with you. Best wishes.

Diet? burning mouth?: balanced diet? try zinc tablets perhaps?? with cheilitis and past stomach resection vitamin B12 deficiency could be a possibility. Burning mouth syndrome might be on the differential diagnosis of what you COULD have.... remind your PMD of your history of stomach surgery, see if they think further testing is needed or referral to an otolaryngologist (ENT) or other specialist