How Does Hetlioz Compare to Melatonin to Treat Non-24

New Medication Previously Compared to Placebo

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When new medications become available, it is natural to question how they might compare in effectiveness to those treatments that are already available. In the case of Hetlioz, sold under the generic name tasimelteon, it’s important to evaluate its usefulness in treating Non-24-Hour Sleep-Wake Disorder (Non-24). How does it compare to melatonin, the standard treatment for this disorder?

Research Comparisons Between Hetlioz and Melatonin

There have been no clinical research trials that compare the use of Hetlioz and melatonin in a head-to-head fashion. The U.S. Food and Drug Administration (FDA) approved Hetlioz based on placebo-controlled trials. This means that Hetlioz, which acts on receptors in the brain for melatonin, was more effective for treating Non-24 than placebo pills. Its effectiveness has not to this point been directly compared to taking over-the-counter melatonin, which has previously been the standard of care for this condition.

Standard Recommendations for Treatment

In its last guidelines from 2007, prior to the availability of Hetlioz, the American Academy of Sleep Medicine (AASM) recommends the use of melatonin for the treatment of Non-24. In order to stabilize the genetically determined circadian rhythms that can lead to cycles of insomnia and excessive sleepiness, melatonin can be highly effective. This stabilization is called entrainment. The rhythms of sleep and wakefulness in blind people can be aligned, or entrained, to the natural day-night patterns.

This can be accomplished with very low doses of over-the-counter melatonin. It is important to select a reputable manufacturer that ensures the quality and precise contents of the product. In general, small doses (0.3 mg) can be used for entrainment of blind people with Non-24. In comparison, many supplement products often contain 3 mg of melatonin (10 times as much as is required) or even more. This excessive melatonin may flood the system, counteracting the benefits and potentially leading to side effects.

The timing of the melatonin dose is critical. It may require the assistance of a sleep specialist to ensure that the dose amount and timing are appropriate.

Assessing the Treatment Effects

How do you know if the treatment is working? Beyond symptomatic improvement, it can be helpful to track the treatment’s effectiveness in other objective ways. Sleep logs and laboratory measurements of circadian phase markers can be useful.

Importantly, in people with Non-24 who are not totally blind, timed light exposure may be a helpful adjunctive therapy.

Hopefully further research will make direct comparisons between Hetlioz and melatonin, but in the meanwhile you may consider discussing the treatment options with your sleep specialist to determine the best option for you.


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