Before you give baby any meds, always check in with your pediatrician. Benadryl should not be given to children under the age of 2.
The FDA says children under 2 should never be administered cough and cold medicine containing the decongestants ephedrine, pseudoephedrine or phenylephrine, and the antihistamines diphenhydramine (found in Benadryl), brompheniramine or chlorpheniramine. The FDA also reminds parents never to modify dosages intended for older children.
Even children between 2 and 5 years old should not take Benadryl unless a doctor has directed them to do so. Kids between ages 6 and 11 can take between 5 milliliters and 10 milliliters every four to six hours.
Benadryl has a sedative effect (which is why it’s so important to stick to the proper dosage!), but it should be used only to treat allergies and never to help children fall asleep.