Patients with allergic purpura who experience leg pain indicate the development of the arthritic type of allergic purpura. Firstly, strict bed rest should be enforced in daily life to reduce the burden on the joints. Secondly, active treatment of the primary cause of allergic purpura should be pursued, which can include taking medications like desloratadine dispersible tablets to reduce the rash. Subsequently, anti-inflammatory and analgesic drugs, such as diclofenac sodium sustained-release tablets, can be taken to alleviate leg pain. If the symptoms do not significantly improve with these measures, the use of a small dose of corticosteroids may be considered if necessary. (Medication should be administered under the guidance of a professional doctor.)