Long-term use of anti-tuberculosis drugs can be harmful to the body because most anti-tuberculosis drugs have side effects, commonly in the liver, which can cause liver damage and abnormal liver function. In addition, common side effects include gastrointestinal irritation, decreased white blood cells, and allergies, such as rashes and peripheral neuritis. If symptoms of gastrointestinal irritation occur, anorexia and abdominal distension are seen. When the symptoms are not severe, no special treatment is required. In case of liver damage, liver-protective drugs can be given, but in case of severe liver damage, anti-tuberculosis drugs need to be stopped. Some drugs cause more serious liver damage, such as rifampin. Isoniazid mainly causes peripheral neuritis as a side effect, and pyrazinamide can mainly lead to increased blood uric acid and induce gout. Ethambutol can damage the optic nerve and cause blurred vision.