H2 receptor blocker(H2受体阻断剂) CH2-CH2-NH2 HO CH2-CH2-NH2 N N ○ Histamine Serotonin CH2一N CHa CH2SCH2CH2N =CNHCH3 N N HN一C=N CHa Cimetidine Ondansetron Cimetidine(西咪替丁) A histamine H2-receptor antagonist that inhibits the production of acid in the stomach.It is largely used in the treatment of heartburn and peptic ulcers.Approved in 1976,it is marketed under the trade name Tagamet. Cimetidine is a known inhibitor of many isozymes of the cytochrome P450 enzyme system,specifically CYP1A2, CYP2C9,CYP2C19,CYP2D6,CYP2E1,and CYP3A4. This inhibition forms the basis of the numerous drug interactions that occur between cimetidine and other drugs.For example,cimetidine may decrease metabolism of some drugs. 44 H2 receptor blocker (H2 受体阻断剂) A histamine H2-receptor antagonist that inhibits the production of acid in the stomach. It is largely used in the treatment of heartburn and peptic ulcers. Approved in 1976, it is marketed under the trade name Tagamet. Cimetidine is a known inhibitor of many isozymes of the cytochrome P450 enzyme system, specifically CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4. This inhibition forms the basis of the numerous drug interactions that occur between cimetidine and other drugs. For example, cimetidine may decrease metabolism of some drugs. Cimetidine (西咪替丁)