Nasty Taste in Mouth

I'm currently on a juice fast. This is not my first fast. But this is the first time I've experienced a nasty taste in my mouth. This is beyond the usual bad breath that happens with normal detox. Instead of bothering other people (as with bad breath) it's bothering me! It's like something is in the back of my throat and refuses to be coughed up. It tastes like the nasty pink medicine we were given as children. It's making me quite nauseous.

Any advice?