The side effects of Xithromax are mainly in the digestive system, nervous system and cardiovascular system, etc. The generic name of Xithromax is Astemizole, which is an anti-allergy drug. After oral administration of Astemizole, symptoms such as dry mouth, nausea, abdominal distension, abdominal pain, diarrhea, and increased appetite may occur, and long-term use may lead to weight gain. In addition, individual patients may experience impairment of liver function after taking Astemizole, which may lead to hepatitis in severe cases. Astemizole can cause cardiac arrhythmia, so if you experience panic, chest tightness, or chest pain while taking the drug, please seek medical attention immediately. Astemizole can also cause headache, dizziness, drowsiness, fatigue, and in severe cases, impaired consciousness, convulsions, inattention, and dyskinesia, so you should avoid driving or engaging in dangerous overhead work while taking the drug.