After colonoscopy generally does not cause the occurrence of low fever, the occurrence of low fever should be considered non-infectious and infectious factors. 1. Non-infectious factors: low fever may be caused by some diseases, such as hyperthyroidism, systemic lupus erythematosus, tumors and so on, and some patients may also have low fever after taking medicines. 2. Infectious factors: the human body is susceptible to bacterial and viral infections when the immune system is low, resulting in low-grade fever, if accompanied by coughing, sputum and runny nose, the cause of the disease should be clarified in time. It is recommended that after the colonoscopy patients should not be too nervous, if the low fever continues to be unrelieved, it is necessary to consult a doctor in a timely manner, under the guidance of a professional physician to clarify the cause of the disease, do not blindly take medication.