About melatonin
Melatonin is both a hormone that your own body makes as well as a supplement you can buy without a prescription. Melatonin influences the timing of your circadian rhythm. The human body begins producing melatonin about 5 hours before a person's habitual bedtime. If your bedtime varies a lot, so will the onset of melatonin production, and so too will the timing of your circadian rhythm. Exposure to bright light (particularly the blue portion of the light spectrum) suppresses the body's production of melatonin. Common sources of such blue light are electronic devices (e.g., TVs, computers, cell phones). So, both an irregular sleep schedule and evening light exposure can increase the risk of insomnia because of the negative effects they have on the timing and amount of melatonin the body makes. For more information about how to limit exposure to blue light in the evening, see the following page: circadian rhythm.
People who are disposed to be "night owls" tend to have a later onset of melatonin production while people who are "early birds" tend to have an earlier onset. The bodies of older adults (i.e.>60 years old) may produce somewhat less melatonin than younger adults.
Supplemental melatonin
A melatonin supplement can be taken on a regular basis to influence the timing of a person's circadian rhythm. It can be a very helpful treatment for older adults with insomnia. In addition, "night owls" who want to be able to go to sleep earlier can use it to help shift the timing of their circadian rhythm (in addition to limiting blue light exposure in the evening). ("Early birds" who want to stay up later can expose themselves to bright light in the evening to delay the onset of their body's melatonin production).
Supplemental melatonin comes in lower dose tablets (<1 milligrams [mg]) and higher dose tablets (>1mg). In local supermarkets and drug stores, it is common to find higher dose versions (such as 3mg, 5mg, and 10mg) but not lower dose versions (such as 300 micrograms [mcg]; which is one-third of a milligram).
The expert consensus is that melatonin taken at higher doses is not very effective as a treatment for insomnia. Higher doses, particularly if they are taken inconsistently and a different times at night, can actually be detrimental to sleep because they can throw off the timing of circadian rhythm. If you are going to use melatonin, it is best to get a low dose version and take it every night at the same time. Because lower dose melatonin is often not carried in local stores, it might need to be obtained online.
Low-dose timed melatonin
A commonly used strategy to positively influence a person's circadian rhythm is to take 300 micrograms (mcg) five hours before an intended consistent bedtime and take 600mcg at bedtime. This is a particularly appropriate strategy for night owls who want to be able to maintain an earlier bedtime.
An alternative to this strategy is to obtain a specially formulated timed-release product called REM Fresh (www.remfresh.com). This formulation releases melatonin for up to 7 hours, and reportedly better mimicks the body’s natural release of melatonin. It comes in .5, 2mg, and 5mg versions. Because it is timed-release, I would be less concerned about negative effects from higher doses. The instructions for the product recommend taking it 30 to 90 minutes before an intended consistent bedtime.
Side-effects, contraindications, and interactions
For more information about melatonin, including side-effects, contraindications, and interaction effects with other medications see WebMD. Please read this information before deciding whether to use melatonin, and consult with your primary care physician if you have a condition on the "contraindications" list or are taking another medication that could significantly interact with melatonin.