Why do sleep aides ambien, lunesta, (eszopiclone) prosom work?

They slow: The activity of the brain which promotes sleep.

Sleep medications: They all work through their sedative/ hypnotic effect to promote sleep.

It would be best to discuss this with your Psychiatrist. If you are not confident with your Doctor see another for a second opinion. It's good to have a physical exam to rule out illness. Sleep is very important for physical and mental health. You may need a sleep study to determine why you can't sleep. Also consult with a Clinical Psychologist with expertise in multiple types of psychotherapy.