It doesn't sound like pertussis. It sounds like she has a regular old cough. If she has no cold sxs perhaps she is allergic to something in the house?
More concerning is the advice to give a 4 month old Benadryl and Mucinex!! No way I would do that!! Hylands makes a homeopathic cough syrup for babies.
Rub vicks on her feet and cover with socks before you put her to sleep - that always worked wonders for us. Honestly that cough doesn't sound that bad at all. I know its tough to hear our babies coughing but coughing is a protective thing and doesn't always need to be treated. Is it waking her up and preventing her from sleeping?
Hang in there! I know its tough when they are small. My DD has what the docs think was RSV a few months ago. While she was older than yours at 10 months, the cough was gross and I'm a worrier by nature - not a good combo!
Wow, when my DD had a reaction to oats at 10mos and was covered in hives and swollen, the 24hr dr number wouldn't even give me a dose for benadryll bc she was too young! That I handled with rescue remedy, but that's a bit different than a cough.I can't think of the brand but I have a natural version of vicks that uses coconut oil as the base and it works great on the feet with sock - even used it myself this winter! A nice steamy bath with eucalyptus/pepermint oils helps too.
How she doing now Jen6163??
that's the usual scenario!
With the RSV (or whatever it was) - it took my DD almost a month to get better!