Melatonin Side Effects: What Are They?

by Dr. Gregory Brown

The sleep disorder insomnia is increasingly prevalent throughout the world, affecting men and women of all ages. Melatonin pills for insomnia have become a popular sleep aid in recent years. But before you start taking melatonin, it’s important to understand how it works to promote sleep, along with any potential dangers or risks that might be present.

The definition of insomnia is not being able to get enough restorative sleep, even though there is adequate time and opportunity for sleep. Insomnia is usually divided into three types: 1) temporary, 2) acute, and 3) chronic.

The causes and symptoms of insomnia vary from person to person, making it harder for doctors to arrive at accurate diagnoses. To complicate matters further, insomnia can happen rarely, it can be a regular occurrence, or it can even develop into a chronic condition.

Doctor-prescribed medications for insomnia often contain melatonin. Sleep aids containing this ingredient may have side effects that many people are not fully aware of and should therefore take care to understand fully. This will be explained in detail below, but first let’s look at two common types of insomnia:

Sleep Onset Insomnia

Sleep disorder causes are often complex and interrelated, and are different from individual to individual. The most prevalent type of insomnia is known as sleep onset. As a general rule, sleep-onset insomnia is seen more often in younger people, while sleep maintenance insomnia occurs more often in older people.

Common causes of sleep onset insomnia include changes in one’s lifestyle, sources of temporary stress (like an exam or work deadline), drinking coffee or caffeinated drinks before going to bed, or a lack of exercise. Anxiety sufferers often report disturbances in onset sleep latency. (In other words, the period of time in which a person falls asleep at night becomes longer, which leads to even more anxiety.)

Generally speaking, when a person can’t fall asleep when they want to, they are exhibiting symptoms of sleep-onset. This form of insomnia is often caused by stress and not being able to relax and calm one’s mind after going to bed.

Sleep Maintenance Insomnia

On the other hand, sleep maintenance insomnia is manifested when a person wakes up often in the middle of the night. This is a common and frustrating sleep pattern that affects millions of people. Sleep maintenance insomnia usually affects people as they get older, starting around 40 years of age.

Here are some symptoms of sleep maintenance insomnia:

• Sleeping for only a few hours, then waking up and being unable to fall asleep again.
• Waking up suddenly in the middle of the night, and then can’t fall asleep again.
• An “in-between” state of sleep where one feels “half awake” despite being asleep.
• Waking up too early, and then being unable to fall asleep again.
• Awakening frequently for brief periods throughout the night.

Melatonin for Insomnia

Melatonin has been shown to have important effects on sleep, especially in the timing of sleep known as the circadian rhythm. Melatonin is produced within the brain in a gland called the pineal gland.

Over-the-counter supplements that contain melatonin have become popular in recent years for people who are trying to improve their quality of sleep. Melatonin supplements usually contain between 1 and 2 milligrams of melatonin, most often in tablet form.

Sleep medicines containing melatonin have been proven effective in scientific research studies, although their use for extended periods of time is not recommended. Given that many sleep disorders are the result of psychological issues, learning how these influence one’s sleep patterns is vital if a person wants to cure their insomnia.

Melatonin Precautions

Melatonin is a hormone that is produced naturally in the body, and its side effects can usually be managed without incident. Nevertheless, there are certain precautions to be observed. Depending on which country you live in, a complete medical history may be necessary before obtaining a prescription for melatonin.

Individuals with a history of liver or kidney disease will normally be advised to not take melatonin. Pregnant women or mothers who are breastfeeding also risk complications from taking melatonin. On the other hand, people who seek relief for restless legs may want to try melatonin tablets.

Melatonin research continues and firm conclusions are not yet available. Given that melatonin treatment can only bring short-term relief for sleeplessness, some doctors may hesitate to prescribe or recommend it, preferring to address the root causes as to why a patient has trouble sleeping.

Side Effects of Melatonin

Most of the time, melatonin side effects will be nothing more worrisome than making a person feel drowsy. Needless to say, one should avoid driving or operating heavy machinery while taking melatonin.

Other melatonin side effects may include becoming angry or irritable, experiencing migraine headaches or having dizzy spells. All of these are symptoms of sleep deprivation, so it’s important to communicate with one’s doctor if and when they occur.

If stomach pain or constipation are experienced, stop taking melatonin and other medications and immediately see your doctor. Weight gain while taking melatonin is another issue that should be discussed with one’s doctor as soon as possible.

While they do occur, melatonin side effects are fairly uncommon. There are also other good treatments for sleep disorders, so if a person lacks enough restorative sleep they should see their physician and discuss the available treatment options.

(published January 4, 2011)