40 days of the baby’s buttocks red, may be due to the number of times the diaper wear too much friction caused by the number of times you should reduce the wearing of diapers; there may be due to the stimulation of the stool residue caused by the suggestion of timely cleaning of the buttocks. 1. Diapers due to: due to wear diapers too many times, walking back and forth friction, poor breathability caused by buttocks red, it is recommended to minimize the number of times during the day to wear diapers, to keep the buttocks dry and clean, or to the baby’s buttocks to apply some erythromycin ointment to prevent infections, the symptoms will slowly improve. 2. Residue stimulation: If the baby’s stool is too many times, leaving residue, can also cause red buttocks, suggest that the baby every time after the stool in a timely manner with lukewarm water to clean, and then partially dry, so as to avoid skin inflammation. This kind of situation is recommended to go to the regular hospital for diagnosis and treatment. The above drugs need to be used under the guidance of a doctor.