HomeSleep ScienceThe Essential Melatonin Guide and How to Use it Safely

The Essential Melatonin Guide and How to Use it Safely

By - Last Updated: July 20th, 2019

Getting good quality sleep is increasingly difficult in our stressful society.

Many people seek out natural remedies to help them get more shut-eye. One such widely available remedy is the supplement, melatonin.

I myself have used melatonin to get over jetlag and help me alter my sleep schedule.

But before taking any drugs or supplements, it’s important to know exactly what you’re putting into your body and how it works.

Below is my complete overview of melatonin, how it affects sleep, and how to take it safely.

Table of Contents

What is Melatonin?

Melatonin is a naturally occurring hormone in animals and humans. Its main role is to coordinate your sleep/wake cycle by communicating information about the light in your environment to your brain.

Chemical structure of the hormone melatonin
The chemical structure of melatonin

How is Melatonin Synthesized?

Incoming light signals travel through your eyes and help the brain maintain your 24-hour biological cycle, known as the circadian rhythm.

Your circadian rhythm regulates your sleep-wake cycle and various other biological processes, such as eating and hormone release, that occur within a 24-hour time period.

Melatonin is Created by the Pineal Gland

During the day, light enters your eyes through the retina and stimulates a small area in your brain of your brain called the pineal gland. When the pineal gland stops receiving light stimulation, it produces melatonin.

The location of pineal gland in the brain.

Melatonin is synthesized (created) from the neurotransmitter, serotonin within the pineal gland.

How Does Melatonin Help You Sleep?

In the evening when it gets dark and your eyes receive less light input, your pineal gland ramps up production of melatonin.

The hormone doesn’t affect you in the same way as sedatives or sleeping pills. Instead, it acts as a messenger that informs the brain when it’s time to sleep or wake.

Increasing levels of melatonin signals to your brain and body that it’s time for bed and you’ll start to feel sleepy.

Melatonin gradually increases and reaches its peak in the middle of the night. After its peak, the pineal gland stops its production of the hormone. Falling levels of melatonin signal to the brain that it’s almost time to wake.

What Happens When Melatonin Production is Altered?

Disruption to your melatonin synthesis has serious consequences for your sleep. Below I’ll describe the most common reason melatonin levels become altered.

Melatonin and Blue Light

As I described above, melatonin levels are regulated by light information entering our eyes and stimulating the pineal gland.

Humans evolved over thousands of years relying only on the light on the sun and the gentle light of a fire.

The recent introduction of electricity means that we’re now constantly exposed to incoming light information from lightbulbs and electric screens.

Artificial blue light from electronic devices closely mimics sunlight. These bright lights inhibit your feeling of sleepiness by reducing the production of melatonin, stimulating your brain to stay awake.

Cartoon of brain in head with light from sun and cell phone entering eyes and reducing melatonin production by the pineal gland
Reduction in melatonin production by the pineal gland when light enters the eye.

The Effects of Blue Light on Health

The use of electronic screens at night is associated with difficulties falling asleep (insomnia), poor quality sleep, the development of mental illness, and an increased risk for health conditions such as heart disease and diabetes.

Limiting Blue Light Exposure at Night

Discontinuing use of blue-emitting screens two hours before bedtime is the best way to prevent disruptions to your melatonin production.

Some companies offer products that filter blue light. If you absolutely must use screens before bed, try using blue light blocking glasses made specifically for night time use.

I personally like the BioRhythm Safe(TM) nighttime blue light blocking glasses. Not only do they filter out most incoming blue light but their tint is made to help relax your eyes before sleep.

Last updated: 2020-04-02 / Affiliate links / Images from Amazon Product Advertising API.

How to Use Melatonin Supplements to Improve Sleep

Melatonin can be produced in a laboratory in the form of an oral supplement and can be taken to help improve your sleep.

Some studies found that use of melatonin before bed can reduce the amount of time it takes to fall asleep and decreases the number of mid-sleep awakenings.

Melatonin is well tolerated at and has no major side effects at low doses. It can be purchased over the counter in most pharmacies across North America.

Properly Using Melatonin Supplements

Melatonin is commercially available for the use of helping improve sleep in healthy individuals.

While melatonin supplements are generally considered safe and useful for a variety of sleep issues, it should always be taken with caution.

Unlike prescription medication, over the counter (OTC) melatonin supplements are not regulated by the U.S. Food and Drug Administration (FDA). This means that OTC melatonin may not have a consistent amount of the active ingredient. Strength may also vary greatly between brands.

For example, if you take 5 mg OTC melatonin, it may actually contain considerably more or less of the hormone than listed. Depending on how the supplements are manufactured, they may also be absorbed into the bloodstream at different rates.

Always consult with your doctor before taking OTC melatonin supplements.

Types of Melatonin Supplements

Melatonin is available in both solid and liquid forms.

There are five types of OTC melatonin available to purchase in retail stores:

  1. Melatonin Capsules and Tablets
  2. Melatonin Gummies
  3. Melatonin Spray
  4. Liquid Melatonin
  5. Time-release Melatonin

1. Melatonin Capsules and Melatonin Tablets

Capsules and tablets are the most commonly available forms of melatonin and can be easily found in pharmacies across North America. They are usually prefered by adults.

2. Melatonin Gummies

Melatonin gummies are en excellent option for children or adults that have difficulties swallowing pills.

3. Melatonin Spray

Melatonin spray is administered on your tongue by a fine liquid mist. It’s also an excellent option for children or adults with difficulties swallowing pills.

4. Liquid Melatonin

Liquid melatonin is usually delivered orally by an eyedropper onto the tongue. Like gummies and spray, it’s a good alternative to tablets.

5. Time-release (Extended-release) Melatonin

Time-release melatonin is absorbed into your body slowly and extends the total amount of time melatonin stays in your system.

Time-release melatonin is a great option for people who have difficulties staying asleep or getting back to sleep after waking up during the night.

How Long Does it Take Melatonin To Work?

Once you’ve ingested melatonin, the time it takes for the active ingredient to work depends on why you’re using the supplement in the first place.

If you’re using melatonin to help you fall asleep and stay asleep, it takes approximately 30 minutes to reach a maximum concentration in your bloodstream.

If you’re taking melatonin to adjust your circadian rhythm, it can take several nights of use before seeing results.

How Long Does Melatonin Last?

The amount of time melatonin stays in your system is dependent on several factors including your age, weight, sex, and the amount of melatonin you take.

In general, small doses of 1 mg or less are an excellent solution for helping you fall asleep but are unlikely to last for more than an hour. Increasing your dose may maintain melatonin in your system for several hours or more.

Time-release melatonin is an excellent option for people who have trouble staying asleep because it’s absorbed into your body slowly and extends the total amount of time melatonin stays in your system.

How Much Melatonin Should You Take?

In North America Melatonin is available over the counter in the following dosages:

  • Melatonin 1 mg
  • Melatonin 5 mg
  • Melatonin 10 mg
  • Melatonin 20 mg
  • Melatonin 30 mg

Melatonin Dosages for Adults and Children

The recommended dose of melatonin depends on several factors including your age, sex, weight, and why you’re being treated.

I generally don’t recommend using more than 5 mg unless otherwise recommended by your health care professional. 

AgeRecommended Melatonin Dosage
> 181 – 5 mg (> 10 mg: consult with your doctor)
Pregnant WomenAlways consult with your doctor before use.
4 – 181 – 5 mg (> 5 mg: consult with your pediatrician)
0 – 3Always consult with your pediatrician before use.

Melatonin Dosage for Adults

The safest dose of melatonin is the lowest dose that effectively helps you sleep.

Medical professionals recommend that adults start with 1 mg of melatonin. If your sleep doesn’t improve with 1 mg, you can slowly increase your dose to 5 mg. Any dosage over 5 mg should be taken with the guidance of your doctor.

Can Women Take Melatonin During Pregnancy?

Insomnia is extremely common during pregnancy and women often look for remedies to help them get better sleep.

Unfortunately, there is little evidence that proves whether taking melatonin is safe while pregnant.

Also, as discussed above, OTC melatonin is not regulated by the FDA and there is no guarantee of the supplement’s quality, how it’s absorbed, or whether it’s the correct dosage.

If you’re pregnant, you should always consult with your healthcare provider before taking any medicinal supplement.

Pregnant women should consider investigating drug-free alternative treatments for insomnia.

Can Children Take Melatonin?

You should always consult with your child’s pediatrician before giving your child melatonin.

Melatonin in low doses (1-5 mg) is generally considered safe for older children (4+ years) and teenagers. Your child’s pediatrician can help you decide which dose is best for your child and how it’s administered.

Can Young Children and Babies Take Melatonin?

Melatonin has been associated with seizures and other medical complications in young children under the age of four.

You should never give your young child or baby melatonin unless otherwise directed by a pediatrician.

What Time Should You Take Melatonin?

The time you should take melatonin depends on your intended use. Below is a guide on how to correctly time your melatonin use.

What Time Should You Take Melatonin to Help You Fall Asleep?

As discussed previously, melatonin can help you fall asleep faster and reduce your number of nighttime awakenings.

If you’re planning on taking a melatonin supplement to help you get better sleep, you should aim to take it 30 minutes before you go to bed. This will prevent you from altering your circadian rhythm.

What Time Should You Take Melatonin to Adjust Your Circadian Rhythm?

Melatonin can be strategically used to adjust your circadian rhythm by a few hours. Below is a guide on how to shift your biological clock forward or backward.

Nights Owls That Want to Go to Bed Earlier

If you’re a night owl and want to adjust your circadian rhythm to an earlier sleep/wake time, you should aim to take melatonin 2 hours before the time you would like to start going to bed.

For instance, if you normally go to sleep at 1:00 am but would like to start going to bed at 11:00 pm, you should take melatonin at 9:00 pm.

It may take several days for your circadian rhythm to adjust.

Early Risers That Want to Go to Bed Later

If you’re an early riser and want to adjust your circadian rhythm to a later sleep/wake time, you should aim to take melatonin first thing in the morning.

Melatonin naturally peaks in the middle of the night and declines in the hours before you wake. By taking melatonin in the morning, your brain will consider this period to be your melatonin peak, and shift your sleep schedule forward.

You may have to take melatonin for several days before seeing results.

What Time Should You Take Melatonin for Jet Lag?

If you’re planning on travelling across several timezones, you can strategically use melatonin to reduce jet lag.

Decide when you’d like to go to bed at your planned destination. A couple of days before you travel, take melatonin 30 minutes prior to the target bedtime at your destination.

Some professionals believe that using melatonin for jet lag is only beneficial if you’re travel eastward while others believe it can help for travelling in both directions.

SituationRecommended Time to Take Melatonin
For Better Sleep30 min prior to your normal bedtime.
For Night Owls2 hours before your new intended bedtime.
For Early RisersFirst thing in the morning.
For Jet Lag30 min prior to the target bedtime at your destination
for 3-4 days before travel.

How Melatonin Can Help Treat Sleep Disorders

If you have a sleep disorder, your doctor may prescribe the use of therapeutic melatonin to help reduce its severity.

Research suggests that melatonin supplements are helpful for treating a variety of sleep disorders. You should always consult with your doctor before using melatonin alongside your sleep disorder.

Using Melatonin for Circadian Rhythm Sleep Disorders

Circadian rhythm sleep disorders (CRSD) are a group of sleep disorders that dramatically alter your time of sleep.

Most people start feeling tired in the late evening but individuals with CRSD sleep much earlier or later than usual. Abnormal sleep time can also be caused by shift work or jetlag.

Medical studies found that the use of melatonin by itself or in combination with light therapy is useful in the treatment of the following circadian rhythm sleep disorders:

  • Delayed Sleep Phase Disorder
  • Advanced Sleep Phase Disorder
  • Non-24-hour Sleep-wake Disorder
  • Irregular Sleep-wake Rhythm
  • Jet Lag Disorder
  • Shift Work Disorder

Using Melatonin for Insomnia Disorders

Scientists have found melatonin to be an effective treatment for most individuals with primary insomnia.

As you get older, your ability to produce melatonin decreases. Sleep quality generally starts to decline in your 50’s and continues to get worse as you age. Melatonin supplementation is especially helpful for the treatment of insomnia in the elderly.

Clinical trials have also shown melatonin is effective in other groups of insomnia sufferers including:

Using Melatonin for Sleep-related Breathing Disorders

Scientific evidence suggests that individuals with sleep-related breathing disorders (SBD) may not produce enough melatonin at night and dysregulate circadian rhythm.

SBD is also correlated with an increased risk of developing heart disease and diabetes.

Many medical professionals believe melatonin supplementation is helpful in the treatment of both sleep issues and secondary health conditions associated with SBD like sleep apnea.

The following positive effects of melatonin for SBD include:

  • Frequent nighttime awakenings in patients with SBD can alter the circadian rhythm. Melatonin helps to normalize sleep/wake cycles.
  • Studies found that melatonin prevents large spikes in blood glucose that occurs when sleep apnea reduces blood oxygen.
  • Melatonin reduces the risk of developing an enlarged heart caused by chronically reduced low blood oxygen levels.
  • Melatonin inhibits inflammation that occurs with SBD and reduces the risk of heart damage.
  • Hypertension (high blood pressure) is a common side effect of long term SBD. Scientists showed that melatonin normalizes blood pressure.
  • Hypertension leads to reduced blood flow to cells and tissues. Melatonin dilates arteries and increases blood flow.

book icon
Further Reading:
The Complete Guide to Sleep Apnea

Using Melatonin for Hypersomnia Disorders

Very little research has been conducted on the use of melatonin supplementation for individuals with hypersomnia disorders, however, it may be effective in the treatment of narcolepsy.

Patients with narcolepsy have extreme daytime sleepiness (hypersomnolence) due to major dysfunction of their sleep cycle.

Narcolepsy causes individuals to enter the REM stage too soon after falling asleep.

An abnormally high amount of time spent in REM reduces the total time spent in a restorative deep sleep. This makes the patient feel unrested the next day.

Some professionals believe that melatonin alters the sleep architecture in narcolepsy, helping to restore deep sleep.

book icon
Further Reading:
The Definitive Hypersomnia Guide: When Too Much Sleep Isn’t Enough

Using Melatonin for Parasomnia Disorders

Parasomnia sleep disorders are classified as any abnormal events that occur during sleep. This includes nightmares, sleepwalking, and sleep paralysis.

Many parasomnias occur during specific sleep phases, NREM or REM.

As previously mentioned, melatonin can alter sleep architecture. Some scientists think it could be a useful therapy for some parasomnia disorders that occur during specific sleep phases.

Studies have shown that melatonin is a particularly good treatment for REM sleep behaviour disorder (RBD).

People with RBD enact their dreams which can lead to injury to themselves or others. Patients with RBD that were treated with melatonin had fewer injuries and adverse effects.

The Risks of Using Melatonin

There are always risks involved when using any drug. Below is information on the potential hazards of using a melatonin supplement.

How Much Melatonin is too Much?

As above, I generally recommend using no more than 5 mg of melatonin unless otherwise specified by your doctor. It’s not unusual for people to start experiencing side effects when you start taking 10 mg or more.

Dosages of melatonin above 15 mg are usually reserved for treatment of sleep disorders and other medical conditions. Melatonin used for sleep disorders should be heavily monitored by a sleep specialist.

Melatonin Side Effects

When taken at low dosages melatonin is well tolerated. Melatonin side effects are generally minimal.

Common minor side effects include:

  • Daytime Sleepiness
  • Headache
  • Dizziness
  • Upset Stomach and Nausea
  • Diarrhea
  • Brief Change in Mood

Can You Overdose or Die on Melatonin?

It’s possible to overdose on any drug or supplement on high enough quantities. Melatonin overload results in moderate to severe side effects, however, the supplement isn’t known to be a potential cause of death.

If you or a loved one believe you have taken too much melatonin, contact poison control immediately.

Symptoms of melatonin overdose include:

  • Extreme daytime sleepiness
  • Bad headache
  • Dizziness
  • Upset stomach and nausea
  • Vomiting
  • Diarrhea
  • Sudden onset of depression or anxiety
  • Low blood pressure
  • Inability to regulate temperature
  • Seizure
  • Tremors
  • Joint Pain
  • Hyperactivity

Melatonin Interactions With Other Drugs

All supplements have the potential to interact with other medications.

Melatonin may reduce the effectiveness or cause side effects when taking it alongside other drugs.

You should consult with your doctor before taking melatonin if you’re on any of the following prescription medications:

  • Blood pressure medication
  • Anticoagulant or blood thinner
  • Contraceptives
  • Selective serotonin reuptake inhibitors (SSRI)
  • Anticonvulsants
  • Seizure medication
  • Immunosuppressants
  • Steroids
  • Diabetes medication
  • Central nervous system depressants

Melatonin and Alcohol

Using melatonin and alcohol at the same time isn’t recommended.

Combining melatonin with alcohol can result in the following side effects:

  • Extreme drowsiness
  • Dizziness
  • Increased anxiety and irritability
  • Increased heart rate
  • Swelling in the feet and ankles
  • Flushing of the face and chest
  • Chills
  • Trouble breathing