What causes green stool? it is a dark green like an olive green stool no diarrhea what does it indicate?

Normal: Bile changes color as it travels through the intestine. The color generally goes from yellow to green to brown. Green stool usually is that way because it has spent less time in the intestines. Because bacteria in the intestines are responsible for the changing color of the bile, a change in the bacterial population (such as after antibiotics) can also result in changes in stool color.