There are quite a few options for specific kinds of sleeping pills and some sleeping pills serve different purposes, Janet Hilbert, MD, assistant professor at Yale School of Medicine tells Health.

“Sleeping pills work in different ways and have different side effect profiles,” she says. “Some work better for problems falling asleep, while some are better for difficulty staying asleep.”

Sleeping pills can be classified in three different ways:Hypnotics or GABA agonists: These target and activate the GABA receptors in the brain, which promote sleepiness, she says. Medications in this class include Ambien, Lunesta, and Sonata.

Melatonin receptor agonists: These target and activate the melatonins receptors, says Dr. Won. Medications in this class include Rozerem

Orexin receptor antagonists: The newest class of sleeping pills, orexin receptor antagonists inhibit orexin, a neurotransmitter in the brain that promotes wakefulness. Medications in this class include Belsomra and Dayvigo.

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