Clarithromycin is the 6-O-methyl ether of erythromycin A, clarithromycin is a macrolide antibiotic used in the treatment of respiratory-tract, skin and soft-tissue infections. It is also used to eradicate Helicobacter pylori in the treatment of peptic ulcer disease. It prevents bacteria from growing by interfering with their protein synthesis. It has a role as an antibacterial drug, a protein synthesis inhibitor, an environmental contaminant and a xenobiotic.