Bad taste in mouth after everything I eat.

Ok so I don't know if I am the only one going through this but I am 17 weeks pregnant and I get a bad taste after everything I eat and drink! It's so annoying!! I have to have something in my mouth at all times in order to put up with it. Brushing my teeth or chewing gum does not help as that also leaves a bad taste. Is there anything the doctor can prescribed to me for this??? Or has anyone else had to deal with this problem before??? Help please!!