Which of the following medications is commonly prescribed for insomnia?

Ambien, also known as zolpidem, is a medication specifically designed to treat insomnia. It belongs to a class of drugs called sedative-hypnotics, which work by enhancing the effects of a neurotransmitter called gamma-aminobutyric acid (GABA) in the brain. This action promotes sleep by slowing down brain activity, making it easier for individuals struggling with insomnia to fall asleep and stay asleep.

While other medications listed may have sedative properties or be used for anxiety management, their primary indications are not for treating insomnia. For example, Adderall is a stimulant used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy, while Xanax (alprazolam) is primarily prescribed for anxiety and panic disorders but is not specifically indicated for insomnia. Prozac (fluoxetine) is an antidepressant that belongs to the selective serotonin reuptake inhibitor (SSRI) class and is used to treat depression and anxiety disorders, but it is not a first-line treatment for insomnia.

Thus, Ambien is the correct choice for specifically addressing insomnia due to its targeted action and approval for this condition.