Clarithromycin side effects include gastrointestinal reactions, liver damage, central nervous system abnormalities, allergies and so on. 1. Gastrointestinal reactions: nausea, vomiting, diarrhea, abdominal pain, dyspepsia, etc. can occur with high doses. Occasionally, stomatitis and oral candidiasis may occur. 2. Liver damage: manifested as elevated alanine aminotransferase and elevated glutamine aminotransferase. Transient and reversible. 3. Central nervous system abnormalities: transient central nervous system adverse reactions include dizziness, insomnia, vertigo, disorientation, anxiety. 4. Hypersensitivity: rash and urticaria in mild cases. In severe cases, toxic epidermal necrolysis. 5. Others: leukopenia, thrombocytopenia, tooth discoloration, reversible hearing loss, altered sense of taste, and so on. Clarithromycin is a macrolide antibiotic, the use of drugs should be under the guidance of a doctor, not private medication, so as not to cause discomfort in the body.