I got a bad, long, cold when my son was 2 weeks old. Anything I took seemed to make my baby stop sleeping or act weird.. and it wasn't like he was sleeping much to begin with.. so I stopped that.
Try a humidifier, if no humidifier -- putting your head close to a pot of boiling water and breathing it or a steamed up bathroom, honey in some tea, peppermint tea as PP said, extra vitamin C, extra B vitamins, tylenol, gargle with really hot (as hot as you can stand) really salty (this may make you gag, beware) water, try gargling with baking soda water too if you can stand it, get a saline nose spray and use that it'll help clear out your sinuses..
I went all natural.. Like I said anything I took made him act weird. And it wasn't pseudophedrine, either ! Even benadryl seemed to affect him. I don't know if your baby would be affected the way mine was but I didn't like it so I went all natural besides some tylenol.
at 11:19 AM on Sep. 13, 2009