That’s easy: If you start wondering whether it is time for someone to go to the hospital, then it is time for him to go.
If it seems that he is in danger of hurting himself or anyone else in any way, he needs to go to the hospital immediately. This is not a negotiable situation; he must be hospitalized right away where no harm can come to him or those around him. If you cannot get through to his doctor in time, call 911. When the emergency medical technicians arrive, clearly explain that there is a danger that he will harm himself or someone else. If the EMT personnel concur that a danger exists, they can take him to the hospital, where he will be evaluated by hospital doctors.