I have just started to use a Castor Oil Pack. I read where I can keep it, if stored properly, and reuse it. Since it is supposed to draw toxins out, how often should I discard the flannel and make a new one? I don't remember it specifying that anywhere. I know when I did a series of colonics, she kept my in a bag marked with my name. But it was only over the course of a few weeks and just a few times at that. Any input will be greatly appreciated.