Yellow Coating on Tongue: Causes, Symptoms & Solutions

Question
I keep getting this bright yellow coating on my tongue.  It goes away if I scrub at it with a toothbrush, but it usually comes back by the end of the day.  I haven't changed my diet and I don't have any other symptoms.  I just have this persistent bright yellow tongue thing.

I'm going to see a doctor if it keeps up, but I thought I'd try to find out first what could be causing this and how I could get it to stop.  

Answer
Most of the time it is an overgrowth of bacteria or fungus, especially if someone had been on antibiotics for a prolonged period of time.  I would recommend gargling with an antiseptic type mouthwash like Listerine, if that doesn't help, it is worth a trip to the doctor.

Hope this helps...