is lithium withdrawal supposed to be this bad?

my partner is going cold turkey off lithium per doctors request and has been fine for the first 5 days but now is having bad body aches, headaches, feels feverish and is puking. they haven’t been anywhere since quitting lithium so i think sicknesses are completely out of the question so the only other thing i can think of is the withdrawal but i haven’t seen any official sources say that these for sure are symptoms, just other posts on here