Melatonin Supplements: Definition, Uses & Side Effects

Instructor: Rachel Torrens

Rachel is a Nurse Practitioner with experience working as a high school teacher, skin surgery center, and as a family NP.

Feeling tired? Well, it's probably because your melatonin levels are rising, but that's not the case for everyone! In this lesson learn all about the uses for melatonin supplementation, and the side effects such supplementation can prompt.

An Elusive Good Night's Rest

It's ten o'clock on a Wednesday night and you're tired. You put on your pajamas, brush your teeth and hop into bed. Ah, time for sweet sleep! But as you lay there with closed eyes, your mind begins replaying the events of the day and you can't sleep. You open your eyes and look at the clock - midnight.

Unfortunately, this is a nightly drama that plays out for many individuals who suffer from insomnia, a condition in which it is difficult to fall or stay asleep. According to the Central for Disease Control, over 50 million Americans suffer from some type of sleep disorder.

Sleep disorders rates continue to rise in the United States.
insomnia image

So why is sleeping so difficult for some? Well, it is a complicated issue and researchers are still trying to pinpoint the origin of some types of sleep disorders. However, most are related to the body's internal clock, also known as the circadian rhythm. Let's explore the details of how this clock prompts a person go to sleep and wake up.

The Mechanism of the Sleep-Wake Cycle

As the sun's rays fade, the pineal gland in the brain becomes more active, secreting hormones to induce sleep. One of these hormones is melatonin. As melatonin levels rise, you feel more drowsy. Hours later, as the sunshine streams into your window, the levels of melatonin sharply decrease, prompting you to wake.

The length of a circadian rhythm ranges from around 24-27 hours, depending on the person. Some people have more melatonin release than others, preferring to go to bed early and rise early. The circadian rhythm is what dictates if you are a ' night owl' or an 'early riser'.

Why Take Melatonin?

Many therapies are on pharmacy shelves to help with sleep disorders, including melatonin. The most common uses for it include:

  1. insomnia
  2. jet-lag due to travel across time-zones
  3. shift-workers

Many people take over-the-counter melatonin supplements to try to promote a healthy sleep cycle.
melatonin supplements image

It makes sense that these are the most common uses for melatonin, as each of these disorders relates to a disturbance in the circadian rhythm. Average doses range from 1 to 5 mg depending on which condition is being treated and on the age of the person taking it.

Melatonin supplementation is meant to be a short-term treatment, just to reset the natural circadian rhythm. Usually no more than 2 months of supplementation is recommended.

Other varied uses exist for melatonin, such as treatment of sunburn, irritable bowel syndrome, infertility, menopause and chronic pain; however, all of these uses still require further research.

Side Effects of Melatonin

Now, just because melatonin is a naturally occurring hormone in the body does not mean it is benign medication. In fact, melatonin supplements are the only hormone available without a prescription (in the US and Canada). Furthermore, the production of this supplement is not regulated by any federal department. So not all melatonin products are equal, and side-effects can vary depending on the melatonin product taken.

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