P.L.
My 16 month old had a dry cough about six weeks ago and I bought this homeopathic medicine from Whole Foods that was recommended to me. I swear I noticed a difference the next day! I would highly recommend you trying it at least. It's in the homeopathic section and is in a blue chap stick-looking tube thingy. There's not a specific dosage for babies, but I just gave Bella three. My friend used it and that's what she used for her 16 month old and it worked for him. They are little pellets, like once used for teething pain. They have them for all different symptoms and there's one for a dry cough and a wet cough. I don't remember the name of it, but just look for dry cough or ask someone. Hopefully, it'll work. Good luck!
Ciao,
P.