What are all possible treatment options for severe depression? what treatments other than ketamine ect can fix severe depression within days or hours

Immediate Evaluation: Severe depression can lead to self destructive behavior (suicidal) Immediate psychiatric evaluation is obviously important, Sometimes hospitalization is first step even if it is short term. There are excellent antidepressant medications but meds often take a few weeks to work sometimes combined with other meds. Psychotherapy is frequently essential which can deal with short and long term issues.