My 19 months old baby has a 100 fever, i gave him an advil (ibuprofen) 2 hours ago, it went down 30 minutes later and now it's getting up again, what do i do?

Treating fever: For fever uncontrolled with Ibuprofen or Tylenol (acetaminophen) alone, alternate Tylenol (acetaminophen) with Ibuprofen, (give Tylenol (acetaminophen) 3 hours after a dose of Ibuprofen and then repeat Ibuprofen 3 hours after each dose of Tylenol (acetaminophen). Be sure to give recommended dose for age & weight of child. A fever of 100 is not dangerous and does not need to be treated unless it is causing discomfort.