
That is, warfarin, also know as Coumadin. And it really can be - in a somewhat different dosage - rat poison. Read here about that.
I took warfarin for years after my stroke in 1998, requiring monthly blood tests to make sure it was effective in preventing blood clots that could lead to a stroke.
Problem is, it also had its own dangers - bruising, bleeding excessively from even a small cut, and internal bleeding, to name a few. I had some pretty ugly bruises myself during my warfarin years.