My 8 week old daughter has an underarm temp of 98.4 should i call the on call pediatrician or just give her a little infant tylenol (acetaminophen)?

Neither: An axillary temp of 98.4 is not be considered a fever, but axillary temps may not be as accurate as rectal. Contact your doctor if rectal temp is 100.4 or higher in an infant under 2 months before giving any Tylenol (acetaminophen). More important is how your baby is behaving with sleep and feedings. If your infant just had a check up and shots, it is common to have slight fever and fussiness. Then meds ok..

Normal temp. : You need not give Tylenol (acetaminophen) because this is not a fever -- normal body temp is 98.6, even when taken in the armpit (despite what you might read in the thermometer packaging). Rectal temps are the most accurate. Any temp over 100.4 is a fever and when this occurs in an 8 week old infant it requires a doctor visit ASAP. Unless your baby is looking or acting ill, you do not need to see a doctor.

Follow for signs: If there are symptoms that prompted you to check the temperature, then these should be communicated to your physician. If your daughter is not feeding well, appears lethargic, or other symptoms, a physician visit is indicated. The temperature readings should be followed and if there is a rectal temperature of 100.4 or higher, a physician visit is indicated.