Baby fever plasters work under certain circumstances, and generally the ingredients used in plasters contain mainly antipyretic and analgesic drugs, such as acetaminophen, ibuprofen, anti-inflammatory pain and other drugs. By applying to the baby’s skin, the drug will be absorbed into the body through the absorption of the mucous membrane to play a role in reducing fever. However, for babies with persistent high fever, such as a body temperature of more than 38.5°C that does not subside, just by applying the cream, it will not work. You should also give your baby enough water, such as feeding warm boiled water and warm juice, to promote urination and sweating to take away body heat and reduce body temperature. If necessary, drugs such as ibuprofen and acetaminophen can be administered orally or by anal suppositories in the form of anal suppositories for better results.