"Lyrium withdrawal causes excessive thirst. In me, and from what I've read, it's fairly common. Fatigue and muscle weakness, especially for the first week or two. Headaches. Deeply unpleasant, but manageable if you plan to stop and make provisions for others to assist you. I imagine involuntary withdrawal, or withdrawal in the field, would have serious dangers." He pauses before he adds:

"It was part of why I did what I did, for what it's worth. Stopping on my terms, in a place where I knew there was an infirmary, at a time that there wasn't a crisis." To avoid the dangers of involuntary withdrawal.