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How fast does melatonin work?

June 16, 2023
4 minutes
Lifestyle Health & Wellness
Sleep wellness strategies

Melatonin is a hormone made naturally by our brains, and its key function is to help us fall asleep at night. What does melatonin help with? Because it has an effect on the body's circadian rhythm—the 24-hour cycle that affects every cell in our bodies—melatonin supplements are helpful for many people who have trouble sleeping.

Some professions and lifestyles take a toll on a person's circadian rhythm. This includes shift workers or people who travel internationally. Additionally, medical conditions or certain medications can also affect a person's sleep patterns. If you are experiencing any of these situations, your medical provider may suggest a melatonin supplement.

Let's dive in and learn all about how melatonin works, when you should take it, and how quickly it will help you get to sleep.

How does melatonin work?

The pineal gland in the middle of your brain produces melatonin. This gland is controlled by a group of nerve cells (neurons) called the suprachiasmatic nucleus (SCN). These nerve cells send signals to each other to control your body's clock.

During the daytime, the pineal gland is in the background and not producing a lot of melatonin. However, when it starts to get dark, the pineal gland goes to work to begin producing melatonin that helps you sleep.

As your body increases its melatonin levels, your blood pressure and body temperature start to drop. The more melatonin you have in your body, the sleepier you'll feel. Basically, melatonin works with your body's natural rhythm to help you feel ready to sleep when bedtime rolls around.

When to take melatonin

Melatonin doesn't knock you out as many prescription sleeping pills do, so it's important to take it about two hours before you go to bed. However, some people may benefit from taking melatonin as late as 30 minutes before bedtime. If you wait too late to take your melatonin, you may feel groggy when you wake up.

How fast does melatonin work?

Does melatonin work right away? The short answer is that your body absorbs melatonin quickly.

Most people produce more melatonin between one and two hours before their regular bedtime and begin to get sleepy. Similarly, if you take a melatonin supplement, you'll probably begin to feel drowsy about two hours later.

In most people, melatonin levels reach their peak about an hour after you take your supplement, so plan on being drowsy in about an hour until you know how your supplements affect you.

Several other factors influence how quickly melatonin works, including the time you take them, your body weight, and other medications you take.

Melatonin is available in all of these forms:

  • Regular melatonin sleeping pills: Active ingredients are released immediately.
  • Extended-release melatonin: Active ingredients are released more slowly than regular melatonin sleeping pills.
  • Melatonin patches: Active ingredients are released more slowly than melatonin pills. Studies have also shown that people who use melatonin patches go to sleep more quickly and sleep for longer.
  • Melatonin gummies: Some studies have found that melatonin gummies absorb better or similarly to pills.
  • Melatonin melts: Melts are dissolved between the cheek and gums or under the tongue. These absorb more quickly than melatonin gummies.

How long does melatonin stay in the body?

Melatonin's half-life is 40-60 minutes. A drug's half-life is the amount of time it takes for your body to eliminate half of the dose.

Most drugs require up to five half-lives to be completely eliminated. With a half-life of between 40 and 60 minutes, this means that melatonin is in your body for about five hours after you take it.

If you remain awake after taking your melatonin, you'll probably feel drowsy. For this reason, you should avoid using heavy machinery or driving after taking melatonin.

Keep in mind that everyone metabolizes melatonin differently and many factors affect how long it stays in your body, including:

  • Caffeine intake
  • Age
  • Tobacco use
  • Body composition
  • Health status
  • Medications
  • Melatonin usage (how often you take it and whether you use extended-release or regular melatonin)

Precautions with melatonin

The most important thing to consider before taking melatonin is that it isn't regulated by the U.S. Food and Drug Administration (FDA). Melatonin supplements on the market have been studied and found not always to contain the dosage the manufacturer lists on the labels. Before buying a product, read reviews carefully and look for supplements that have undergone third-party testing.

While melatonin is widely considered to be safe, there are some precautions to take before starting any new medication, whether prescription or over-the-counter.

You shouldn't take melatonin if any of these apply to you:

  • Autoimmune disease
  • Pregnant or breastfeeding
  • Depression or anxiety
  • Heart or kidney disease
  • Seizure disorder
  • Immunosuppressants or contraceptives

Also, please speak with your medical care provider before taking melatonin if you take any of these because of potential drug interactions.

  • Caffeine supplements (or excess caffeine)
  • Birth control pills
  • Vitex agnus-castus (chasteberry)
  • Antidepressants
  • Anti-seizure medication
  • Blood thinners
  • Blood pressure medication
  • Medication that weakens the immune system

It's important to understand that you shouldn't operate machinery or drive within four to five hours after you take melatonin. If you take sleeping pills or drink alcohol in the evening, don't take melatonin the same night. The combined effects of these substances and melatonin can make you too sleepy and even cause breathing problems.

Melatonin side effects

Like most medications or supplements, melatonin can have side effects. While most health experts believe melatonin is safe for healthy people, its side effects haven't been studied extensively.

These are the most common side effect of melatonin:

  • Drowsiness during daytime hours
  • Dizziness
  • Headache
  • Irritability
  • Upset stomach
  • Temporary depression
  • Intense nightmares

Get well-rested for optimal health

Being well-rested is essential if you want to perform at your best and enjoy a healthful existence. Melatonin can help many people enjoy better sleep.

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