I just saw a honey based natural cough syrup the other day for children 2 and up (I would say 21 months is close if they are average size in weight)
Otherwise just regular honey is supposed to soothe a cough... vaporizer in the room to help with secretions, baby vicks, tyenol and motrin if your baby seems to be achy or feverish
Triaminic also makes a nasal spray that really helps... we use it only before bed if my son is super congested.
Cough meds can be given but ONLY under the direction of your doctor, there are no meds on the shelf with the proper dose for a young child... and you should never guess... so if it's really bad call your ped and see what the suggest.
at 11:31 PM on Dec. 9, 2010