The medical expenses were high, and they didn’t even give me any details or explanations.

Tourists in Japan are not required to have Japanese public health insurance, so medical treatment is provided by medical facilities on the basis of the patient paying all expenses. Public health insurance requires the medical facility to issue the patient a written statement of the medical examination and treatment, but when expenses are being covered by the patient, the medical facility has the choice of whether or not to issue such a report. Ask staff at the reception desk for a detailed statement (meisaisho). We also recommend that you ask for an explanation of each item listed on the issued statement.