Back pain on inspiration may be caused by lung diseases, such as pleurisy, which is due to adhesions between the pleura and the lung tissue due to inflammatory reaction. Therefore, when inhaling due to the increased distance between the two, it may make the adhesion area be pulled and have back pain when inhaling. In addition, be aware of the possibility of pneumothorax and hemopneumothorax. Also be on the lookout for intercostal neuralgia, back muscle pain, etc., which may also be caused by herpes zoster and requires further differential diagnosis.