MELATONIN (N-Acetyl-5-Methoxytryptamine)

Have you ever wondered why you experience jet lag or feel like you can’t fall asleep at night? While there could be other causes, melatonin may be the culprit. Melatonin is a natural hormone that plays an important role in sleep. Production and release of melatonin is related to the time of the day; it is higher in the evening and lower in the morning.1 The National Institutes of Health (NIH) predicts that approximately 30% of the population in the United States has trouble falling asleep (also called insomnia). The effects of insomnia include decreases or limitations in physical functioning, bodily pain, general health perceptions, vitality, social functioning, emotional health problems, and overall mental health. In addition to insomnia, melatonin has also been proven effective in treating jet lag, delayed sleep phase disorder (a disruption of the body’s biological clock in which a person’s sleep-wake timing cycle is delayed by 3 to 6 hours), and shift work disorder.1

What dose of melatonin should you take?

Delayed sleep phase syndrome (DSPS): Melatonin 0.3 to 5 mg daily for up to 9 months has been used.

Insomnia: For primary insomnia, controlled-release, fast-release, or slow-release melatonin 2 mg to 3 mg before bedtime for up to 29 weeks has been used in most research.

Jet lag: Melatonin 0.5 mg to 8 mg, taken at bedtime on the arrival day at the destination and continuing for 2 to 5 days, is commonly used. However, doses greater than 5 mg do not seem to be more effective than 5 mg dose. Low doses of 0.5 to 3 mg are often used to avoid the hypnotic properties of the higher 4 to 5 mg doses.3

Melatonin is not solely used for treating insomnia or sleep related disorders. It can also be sued for benzodiazepine and nicotine withdrawal. Melatonin is also used orally for Alzheimer’s disease or dementia, bipolar disorder, chronic fatigue syndrome (CFS), chronic obstructive pulmonary disease (COPD), beta-blocker-induced insomnia, endometriosis, tinnitus, depression or seasonal affective disorder (SAD), mild cognitive impairment, nonalcoholic steatohepatitis (NASH) and other problems.2 You should check with your doctor before using melatonin for any of these other diseases.

A bottle of melatonin 3mg tablets manufactured by Solgar.

The safety of melatonin has been proven to be effective when used orally or parenterally for short-term or as a single dose. Melatonin is generally well tolerated when taken by mouth. The most common side effects reported are headache, dizziness, nausea, and drowsiness. It is also advised that it may cause daytime sleepiness; therefore, people should avoid using machinery or performing other dangerous tasks, like driving. Other side effects such as transient depressive symptoms, mild tremors, mild anxiety, abdominal cramp, irritability, reduce alertness, disorientation, and hypotension (low blood pressure) have also been reported.3

Melatonin should be used with caution if you are taking any prescription medications such as: birth control pills, fluvoxamine (Luvox), anti-diabetic agents, anti-hypertensive agents, immunosuppressants, medications that lower seizure threshold, anticoagulants or antiplatelet agents, medications that prevent seizures, methamphetamine, any central nervous system (CNS) depressants or benzodiazepines. Herbs and supplements may also negatively impact melatonin. Caffeine, echinacea, herbs and supplements that might lower blood pressure, lower seizure threshold, slow blood clotting, increase sedation, St. John’s wort, and vitamin B12 have moderate interactions with melatonin.3

At Community Farmacy, we offer a variety of over-the-counter products. Melatonin is available as a non-prescription product, and it may be purchased over-the-counter. One product sold by Solgar is one of the best and most cost-effective melatonin products we carry. Melatonin dosage strengths range from 1 mg up to 10 mg or more. However, it is not regulated by the U.S. Food and Drug Administration (FDA). If you have any questions regarding melatonin, please call us or stop in – one of our friendly pharmacists will be more than happy to answer any questions you might have!



  1. Melatonin. WebMD.
  2. Melatonin. National Institutes of Health.
  3. Melatonin. Natural Medicines Comprehensive Database. Therapeutics Research Center.,-herbs-supplements/professional.aspx?productid=940
Written by Kamal Patel, PharmD Candidate, Class of 2018, University of Maryland Eastern Shore School of Pharmacy.