The 27-year-old had started every Premier League game of the season before Saturday's goalless draw with West Ham United, in addition to being included in Gareth Southgate's England squad for the World Cup qualifiers in June and October.
Livermore will now miss Wednesday's EFL Cup clash with Manchester City but could return to face Arsenal at the Emirates Stadium next Monday.
"He is such a good player for us that we don't want to risk him going into a deeper, deeper, deeper hole," Pulis told reporters.
"We had a chat with Jake at the beginning of the week. Jake came to see me. He has felt a little bit jaded, mentally more than anything else.
"We check all of his running stats, and his data, and he had dropped off a bit. I think playing all the time has really, really taken it out of the boy."
Livermore tested positive for cocaine in 2015, almost a year after his newborn son Jake Jnr died.