The study also shows that Rozerem left its users both mentally and physically unimpaired, even at doses that were 20 times higher than recommended.
The FDA approved Rozerem in July 2005 as the first and only noncontrolled prescription drug for the treatment of insomniainsomnia in adults, largely due to the findings, which were first reported a year and a half ago.
Takeda Pharmaceuticals, which manufacturers the drug, kicked off an aggressive direct-to-consumer ad campaign a few months ago featuring the "dream" characters Abe Lincoln and a talking beaver telling a sleep-deprived man that his dreams missed him.
"In many respects the other sleep medications on the market are basically 'me too' drugs," study researcher Roland R. Griffiths, PhD, tells WebMD. "There are subtle differences between them, but they all work in basically the same way and have the same side effects. This drug is completely different."
Former Abusers Didn't Get High
The side effects of traditional sleep drugs include a potential for abuse, as well as physical and mental impairment. Long-term users may also experience withdrawal symptoms when they stop taking these drug, including anxiety, irritability, and even seizures.
To determine if any of these side effects occur with Rozerem, Griffiths and colleagues from Johns Hopkins School of Medicine in Baltimore, Md., enlisted 14 adults with histories of sedative abuse.
The participants stayed at a residential research unit for 18 days, where they were treated each day in random order with either Rozerem in varying doses, the sleep drug Halcion in varying doses, or a placebo.
Throughout the day, the participants were questioned about how they felt on the drug, including whether they felt alert, sleepy, or high. They were also observed by researchers trained to detect behavior changes.
None of the doses of Rozerem tested, including one that was 20 times the recommended dose, showed any difference from the placebo in terms of physical impairment and impairment in thinking and memory.