Sarri is recovering from pneumonia and underwent further tests on Thursday.
Juventus says they "showed a good clinical improvement" but the 60-year-old Sarri needs to be absent "to completely recover."
Sarri has still been going to Juve’s training ground and watching the sessions on video link and co-ordinating with his staff.
Juventus kicks off its bid for a record-extending ninth straight Serie A title at Parma on Saturday, before hosting Napoli the following week.
Sarri spent three seasons at Napoli before moving to Chelsea in 2018.