Generally speaking, a body temperature of less than 36 degrees in adults is called hypothermia, which may be related to the environment, antipyretic drugs, and may also be caused by hypothyroidism. 1. Environment: If the temperature is too low for a long time in the environment, to a certain extent, it will affect the thermoregulation center, which will lead to hypothermia, and the body temperature is lower than 36 degrees. 2. Fever-reducing drugs: If the patient was originally in a high fever state, after taking ibuprofen or acetaminophen and other fever-reducing drugs, it may also lead to a transient decrease in body temperature, which can be manifested as a body temperature of less than 36 degrees. 3. Hypothyroidism: This disease is related to autoimmune thyroiditis, thyroid surgery, pituitary disease, iodine deficiency, congenital hypothyroidism and other causes. Common symptoms include weakness, less sweat, low body temperature, etc. So some patients have body temperature below 36 degrees. There are more reasons for the patient’s body temperature to be lower than 36 degrees, if there is no recovery for a long period of time, the patient should go to the hospital in time to clarify the specific cause.