There is no established dosage for melatonin that is widely accepted. In addition, experts note that most brands contain impurities that cannot be characterized, as well as dissimilar amounts of actual hormone.
When buying in America, please note that the U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary.
You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Below are dosages used by researchers exploring various disorders. (Summarized from the Mayo Clinic.)
Adults (18 years and older)
|Alzheimer’s disease (sleep disturbances)||0.5||nightly, 1 hr before bedtime|
|Bipolar disorder (sleep disturbances)||10||nightly by mouth|
|Cancer||10 to 50,
most commonly 20
|Circadian rhythm entraining (in blind persons)||5 to10||nightly|
|Critical Illness / ICU sleep disturbance||3||nightly|
|Delayed sleep phase syndrome||5||5 hrs before bedtime|
|Depression (sleep disturbances)||5||nightly|
|Headache prevention||5 to 10||nightly|
|Hypertension||1 to 3||short periods of time|
|Insomnia in the elderly||3 to 5||30 – 120 min before bedtime|
|Insomnia of unknown origin (in the non-elderly)||1 to 5||nightly|
|Jet lag||0.1 to 0.5,
5 and 8
|Target bedtime at the destination|
|Schizophrenia (sleep disturbances)||2||(not stated)|
|Seasonal affective disorder||0.25 to 5||daily|
|Sleep enhancement in healthy people||0.1 to 6||30 – 60 minutes before bedtime|
Children (younger than 18 years)
There is limited study of melatonin supplements in children, and safety is not established.
|Circadian rhythm entraining in blind children||2.5 to 10||nightly|
|Preoperative anxiety||0.1, 0.25 or 0.5 per kilogram (of child’s weight?)||(not stated)|
|Seizure disorder in children||5 to 10||nightly|
|Sleep disturbances in children with neuro-psychiatric disorders (mental retardation, autism, psychiatric disorders)||0.5 to 10||nightly|