... abrutly stopped giving her the Amitriptyline for five days. She began having horrible headaches and aggitation, and then I noticed my mistake. I restarted the 40mg of Amitriptyline as soon as I noticed my error. It's been two weeks now that she's been back on it, but she is still feeling horrible and experiencing terrible headaches. I have two questions: 1) Should I have started her back on a lower dose and titrated her back up to 40mg instead of just giving the 40mg right away? and 2) How long do withdrawal symptoms last?