Melatonin : Dosing

by MedlinePlus

(Page 4 of 6)

Standardization

Standardization involves measuring the amount of certain chemicals in products to try to make different preparations similar to each other. It is not always known if the chemicals being measured are the "active" ingredients. There is no widely accepted standardization for melatonin. Experts have noted that most brands contain impurities that cannot be characterized, as well as dissimilar amounts of actual hormone.

In 2002, ConsumerLab.com evaluated 18 melatonin-containing supplements (15 quick-release and 3 time-release products), of which 12 were melatonin-only products. It was reported that 16 of the 18 products contained between 100-135% of the claimed amount of melatonin, one rapid-release product contained only 83% of the claimed amount of melatonin, and another rapid-release product contained a small amount of lead (slightly more than 0.5 micrograms per daily recommended serving size). Among the 12 melatonin-only products that "passed" these standards are: Nature's Bounty® Melatonin 1mg and 3mg tablets, Puritan's Pride® Inspired by Nature® Melatonin 3mg tablets, Twinlab® Melatonin Caps, Highest Quality, Quick Acting 3mg tablets. Further information is available at www.ConsumerLab.com.

Adults (18 years and older)

Alzheimer's disease (sleep disturbances): Studies have evaluated 0.5 milligrams of melatonin taken nightly by mouth one hour prior to sleep.

Bipolar disorder (sleep disturbances): Studies have evaluated 10 milligrams of melatonin taken nightly by mouth.

Cancer: Various doses of melatonin have been studied in patients with cancer, usually given in addition to other standard treatments such as chemotherapy, radiation therapy, or immune therapy. Oral doses have ranged between 10 and 50 milligrams taken nightly, with the most common dose being 20 milligrams nightly. Intramuscular injections of 20 milligrams of melatonin have also been studied. In studies of patients with melanoma, melatonin preparations have been applied to the skin. Patients are advised to discuss cancer treatment plans with an oncologist before considering use of melatonin either alone or with other therapies. Safety and effectiveness are not proven, and melatonin should not be used instead of more proven therapies.

Circadian rhythm entraining (in blind persons): 5 to10 milligrams of melatonin taken by mouth, administered in the evening, has been studied in blind patients to set the circadian rhythm to a 24-hour schedule.

Critical illness/ICU sleep disturbance: Studies have evaluated 3 milligrams of melatonin taken nightly by mouth.

Delayed sleep phase syndrome: 5 milligrams of melatonin given by mouthfive hours prior to bedtime have been studied.

Depression (sleep disturbances): Studies have evaluated 5 milligrams of melatonin taken nightly by mouth.

Headache prevention: Studies have evaluated regular use of 5 to 10 milligrams of melatonin taken nightly by mouth.

Hypertension: Studies have evaluated 1 to 3 milligrams of melatonin taken daily by mouth for short periods of time. Intranasal melatonin (1% solution in ethanol) at a dose of 2 milligrams daily for one week has also been studied.

Insomnia in the elderly: Studies have evaluated melatonin taken by mouth 30 to 120 minutes prior to bedtime for insomnia in the elderly. Low doses (0.1 to 0.3 milligrams taken nightly) appear to be equally effective as higher doses (3 to 5 milligrams nightly).

Insomnia of unknown origin (in the non-elderly): Doses ranging from 1 to 5 milligrams taken by mouth shortly before bedtime have been studied.

Jet lag: Melatonin is usually started on the day of travel (close to the target bedtime at the destination), then taken every 24 hours for several days. Various doses have been used and studied, including low doses between 0.1-0.5 milligrams, a more common dose of 5 milligrams, and a higher dose of 8 milligrams. Overall, 0.5 milligrams appears to be slightly less effective than 5 milligrams for improvement of sleep quality and latency, although this area remains controversial and other research suggests no differences. Slow-release melatonin may not be as effective as standard (quick release) formulations. If the dose is taken too early in the day, it may actually result in excessive daytime sleepiness and greater difficulty adapting to the destination time zone.

Schizophrenia (sleep disturbances): Studies have evaluated 2 milligrams of controlled-release melatonin taken by mouth for three weeks.

Seasonal affective disorder: Studies have evaluated 0.25 to 5 milligrams of melatonin daily by mouth.

Sleep enhancement in healthy people: Various doses of melatonin taken by mouth 30 to 60 minutes before bedtime have been studied and reported to have beneficial effects, including 0.1, 0.3, 1, 3, 5, and 6 milligram doses. Studies report that 0.1 to 0.3 milligrams may produce melatonin levels in the body within the normal physiologic range of nighttime melatonin, and may be sufficient. Research suggests that quick-release melatonin may be more effective than sustained-release formulations.

Other: There are other uses with limited study and unclear effectiveness or safety. Use of melatonin for these conditions should be discussed with a primary healthcare provider and should not be substituted for more proven therapies.

Children (younger than 18 years)

General: There is limited study of melatonin supplements in children, and safety is not established. Use of melatonin should be discussed with the child's physician prior to starting.

Circadian rhythm entraining in blind children: Studies have evaluated 2.5 to 10 milligrams of melatonin taken nightly at the desired bedtime.

Preoperative anxiety: Melatonin 0.1, 0.25 or 0.5 milligrams per kilogram has been studied for alleviating preoperative anxiety in children. Further research is needed to confirm these results.

Seizure disorder in children: Studies have evaluated 5 to 10 milligrams of melatonin taken nightly. Research is limited in this area, and there are other reports that melatonin may actually increase risk of seizure or lower seizure threshold. Therefore, caution is advised, and use of melatonin should be discussed with the child's physician.

Sleep disturbances in children with neuro-psychiatric disorders (mental retardation, autism, psychiatric disorders): Studies have evaluated 0.5 to 10 milligrams of melatonin taken nightly for reduced sleep latency and increased sleep duration. Fast release melatonin may be most useful for sleep induction and the slow release formulation for sleep maintenance.

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