Here's the first nonscheduled prescription sleep aid

Insomnia, a common sleep disorder, affects more than 70 million Americans. According to the National Sleep Foundation's 2005 Sleep in America poll, about 75% of adults have experienced a symptom of a sleep problem a few nights a week or more in the past year.

"Ramelteon has been shown to carry no risks of abuse, withdrawal, or dependency, and negligible risk for next-day hangover effects," said Thomas Roth, Ph.D., director of the Sleep Disorders & Research Center at Henry Ford Health System in Detroit. "It is the first prescription sleep medication that has not been designated as a controlled substance," said Nahmias. Takeda officials said the FDA approval may allow physicians to prescribe ramelteon for long-term use in adults.

According to Nahmias, melatonin has been quite useful in patients with circadian rhythm disorders, jet lag, and delayed sleep phase syndrome. "I would like to see studies performed with ramelteon in these patients to further evaluate its efficacy," he said.

Ramelteon is hepatically metabolized, primarily by the CYP1A2 isoenzyme. The manufacturer advises that ramelteon not be used in combination with fluvoxamine, a strong CYP1A2 inhibitor. The coadministration of the two agents has been shown to significantly increase ramelteon concentrations. Additionally, ramelteon should be administered with caution in patients taking rifampin, ketoconazole, and fluconazole.

The most common adverse events associated with ramelteon in clinical trials were somnolence, dizziness, nausea, and fatigue. Ramelteon has been associated with decreased testosterone levels and increased prolactin levels. Therefore, the package labeling recommends that for patients presenting with any unexplained symptoms possibly associated with these hormone level changes, assessment of prolactin and testosterone levels should be considered appropriate.

The manufacturer cautions that the effect of ramelteon in patients with severe sleep apnea or severe chronic obstructive pulmonary disease (COPD) has not been studied and the drug is not recommended for use in these patients.

The recommended dose of ramelteon is 8 mg, to be taken within 30 minutes of bedtime. Takeda suggests that ramelteon not be used in patients with severe hepatic impairment. However, no dosage adjustments are necessary in patients with severe renal impairment or those who require chronic hemodialysis. Ramelteon is classified as pregnancy category C. It should be used during pregnancy only if the potential benefit to the mother outweighs any risk to the fetus.

Ramelteon should be available for patients in late September.

Monica Shah is a writer and a hospital pharmacist in New Jersey.