Olbas oil


Hi can someone pls help me I'm 10 w +1 and have been suffering with rhinitis and on top a awful cold . I got told to purchase a humidifier to keep me breathing clearer but on its own it does not do much , my question is can I use a few drops of olbas oil in my humidifier? I have heard fantastic reviews but also some that say I can't use it :( ... Shorley In can't do no harm if I used just a few drops in it ??

Many thanks