Taking Gastric Tetralogy with a bitter mouth may be due to an adverse reaction to antibiotics, bismuth and other medications. Gastric quadruple refers to four drugs for the treatment of Helicobacter pylori infection, mainly including omeprazole enteric-coated capsules, colloidal bismuth pectin granules, clarithromycin tablets, amoxicillin dispersible tablets, metronidazole, etc. The human body can experience the adverse reactions of mouth bitterness and taste disorders after taking antibiotics and bismuth, as well as dry mouth and taste abnormalities after taking omeprazole. Adverse reactions of altered sense of smell and reversed sense of taste can occur after taking clarithromycin, and adverse reactions of metallic taste in the mouth can also occur after taking metronidazole. If symptoms of a bitter mouth occur while taking Gastric Tetra for anti-Helicobacter pylori treatment, consult your physician first and do not blindly discontinue the medication on your own.