Are you a doctor? They can cause jaundice and liver damage, and my wife was close to it. I will take their word over someone on a forum any day.
I'm aware of what they can do, they cause your body to absorb less vitamin k. And it would be some rare instances where you could die from gall stones alone.
I would know, I had to live with the damn things for almost a year before they figured out I had Gall Stones, and before they did the surgery for it.
They wouldn't have done the surgery if my vitamin k levels were as low as they were a few weeks to a month before surgery..