ABSTRACTWe report a unique case of a potassium aluminum sulfate oral dissolution leading to palatal chemical necrosis and extensive chemical ulcers on the tongue. The patient, a 47‐year‐old white, blind male, denied using cocaine or other illegal drugs that could cause such lesions. His self‐medication started as a treatment for a traumatic ulcerative lesion on the hard palate. After palatal perforation, he started another self‐medication routine, mixing corticoid cream and tandrilax tablets with a gauze obturator. Our treatment comprised the removal of all chemical factors, a surgical debridement, and a prosthetic obturator to resolve the communication. The 1‐year follow‐up showed no complications.