Acute tonsillitis is an acute infectious inflammation of the tonsils, primarily caused by bacterial infection. Therefore, intravenous therapy is required for acute tonsillitis, which indicates that the symptoms of the tonsillitis are severe, often being suppurative tonsillitis. The duration of intravenous treatment generally lasts about three to five days, but it specifically depends on the patient's condition, and can even last longer. After the infection is controlled and symptoms are alleviated, treatment can switch to oral medications for anti-infection. Overall, there is no specific time rule for how long the infusion should last; it is often determined based on the specific condition of the patient.