Teething medication . It sounds like a good idea. . . to make the mouth numb. But, according to the U.S. Food and Drug Administration (FDA) the topical pain relievers are not effective because they wash out of the child’s mouth within minutes. Also, the FDA warned that if an excessive amount of lidocaine is used, the infants and young children can have seizures, severe brain injury and heart issues.
In addition, the FDA is advising AGAINST the use of over-the-counter topical teething medications for pain.
Want to learn more? http://www.aafp.org/news/health-of-the-public/20140709lidocaineadvisory.html