I saw Ketamine remove depression immediately after a single dose in a loved one. Thought it was magic, because it was, a lifetime of depression just evaporated

I saw Ketamine remove depression immediately after a single dose in a loved one. Thought it was magic, because it was, a lifetime of depression just evaporated like nothing. But then came the psychosis. Nearly got stabbed in my sleep because a voice told them to do that. So... let's just say I think there are other explanations, too.