chloroform
The powder that can make a person unconscious is called "बेहोश करने वाली पाउडर" in Hindi.
These substances are called narcotics.
You make them watch Twilight.
The purpose of itching powder is to make a person itch. The itching powder will make the person feel like they are going crazy.
consult the doctor
There are lots of them, far too many to list here.
If they are unconscious and breathing, nothing will happen. If they are unconscious and not breathing, they will die.
When a diabetic person becomes unconscious, check for their emergency glucagon injection kit, as you are calling 911. Once the person is conscious, treat the same as you would a person who has not been unconscious.
No, it is not possible to be conscious of being unconscious. When a person is unconscious, they are not aware of their state of mind or surroundings.
When the person does not respond
Go to sleep.
Depends on the person and situation.