Getting Amitryptyline isn't the issue. Getting the necessary benzos will be way more challenging unless you have a script. It will also be expensive and you won't know if they're old and won't keep you out while the Amitryptyline does its job. Without the benzos or without a high enough amount, this method will be excruciating if you wake up. The A causes a prolongation of the QT interval in the heart. Which is basically long, slow cardiac arrest leading to death.