What is Melatonin and How Does It Work?


Melatonin is a hormone that the brain produces in response to darkness. The hormone helps with sleep as well as the timing of your 24-hour internal clock, which is known as circadian rhythms. Exposure to light at night can block the production of melatonin.

According to research, melatonin also plays other important roles in the body besides sleep. Those effects, however, are still not yet fully understood.

Melatonin dietary supplements are usually made from microorganisms or animals, but in most instances, they are made synthetically. The information provided below is all about melatonin dietary supplements.


Are Melatonin Supplements Safe to Take?

You should always remember the following when using melatonin supplements:

Interactions with Medications

Just as is the case with all dietary supplements, people taking various medications should first consult their health care providers before using melatonin supplements. Specifically, people with epilepsy and those taking blood thinners should first consult a doctor before taking melatonin supplements.

Possible Risk of Allergic Reaction

People using melatonin supplements may be at risk of allergic reactions.

Safety Concerns for Pregnant and Breastfeeding Women

Research is currently unavailable on the safety of using melatonin supplements by pregnant and breastfeeding women.

Safety Concerns for Seniors

The American Academy of Sleep Medicine released guidelines in 2015 that advised against people with dementia using melatonin supplements. Melatonin may remain active in seniors longer than in younger people and cause drowsiness during daytime.

Products Might Not Contain What’s Listed on the Label

Melatonin supplements might sometimes not contain what is actually listed on the product label. A study conducted in 2017 tested 31 different melatonin supplements purchased from pharmacies and grocery stores.

For the vast majority of those supplements, the quantity of melatonin in the product did not match what was listed on the product label. Furthermore, 26% of supplements contained serotonin, which is a hormone that can have harmful effects even at relatively low quantities.

Are Melatonin Supplements Safe for Children?

Besides the aforementioned issues, it is important to consider certain things regarding the safety of melatonin supplements in children.

Melatonin supplements appear to be safe for most children for short-term use, but there are very few studies on melatonin and children. Furthermore, there’s little information available on the long-term effects on the use of melatonin in children.

Melatonin is a hormone, and it is believed that melatonin supplements may affect hormonal development, including menstrual cycles, puberty, and the overproduction of the hormone prolactin, but it is impossible to know for sure.

Possible side effects of the use of melatonin supplements reported in children are generally mild and include:

- Dizziness

- Headache

- Increased urination in the evening or bedwetting

- Drowsiness

- Agitation


What Are the Side Effects of Melatonin Supplements?


A review on the safety of melatonin supplements in 2015 indicated that only mild side effects were reported in different short-term studies involving adults, critically ill patients, and surgical patients. Here are some of the mild side effects reported in the studies:

- Sleepiness

- Nausea

- Dizziness

- Headaches

The possible long-term side effects of the use of melatonin are still unclear.

Special Precautions and Warnings

Pregnancy

Melatonin supplements are possibly unsafe if taken regularly by mouth or in high doses when trying to get pregnant. It might have similar effects to birth control, which can make it harder to get pregnant.

Currently, there isn’t sufficient reliable information to determine whether melatonin is safe to use when pregnant. Until more is known, it is advisable to avoid using melatonin supplements either while pregnant or when trying to get pregnant.

Breastfeeding

Today, there isn’t sufficient reliable information to determine whether melatonin is safe to use when breastfeeding. So, if you are a breastfeeding mother, stay on the safe side and avoid using it.

Children

Concerns have been raised about melatonin possibly interfering with development during adolescence. Melatonin should ideally be used only by children with a medical need. There is currently no sufficient evidence to determine whether it is safe for children when taken orally, long-term.

Bleeding Disorders

Melatonin supplements can make bleeding worse in people suffering from bleeding disorders.

Depression

Melatonin supplements can make the symptoms of depression worse.

High Blood Pressure

Melatonin supplements have the effect of raising blood pressure in people taking certain medications for controlling blood pressure. If you are one such person, don’t use these supplements.

Seizure Disorders

The use of melatonin supplements might increase the risk of having a seizure.

Recipients of Transplants

Transplant recipients usually take medications to suppress their immune systems. Melatonin can boost immune function, which may interfere with the effects of certain transplant medications.

Moderate Interaction

Melatonin supplements have a moderate interaction with the following substances, which is why you should be cautious when using them in combination.

1. Birth Control Pills (Contraceptive Medications)

Birth control pills appear to increase the amount of melatonin produced by the body. Taking melatonin supplements together with birth control pills can increase the effects and side effects of melatonin.

2. Caffeine

Caffeine can increase or decrease the levels of melatonin in the body. If taken together with melatonin supplements, caffeine appears to increase the levels of melatonin.

3. Fluvoxamine (Luvox)

Taking fluvoxamine can increase the amount of melatonin absorbed by the body. Taking melatonin supplements as well as fluvoxamine can increase the effects and side effects of melatonin.

4. Medications for Diabetes (Anti-Diabetes Drugs)

Melatonin supplements may lower blood sugar levels. Diabetes medications taken along with melatonin can cause blood sugar levels to drop too low. People with diabetes should monitor their blood sugar closely when taking melatonin.

5. Medications that Decrease the Immune System (Immunosuppressants)

Melatonin can increase immune system activity. Some medications, such as those used after transplants, have the effect of decreasing immune system activity. Taking melatonin supplements along with such medications can decrease their effects.

6. Medications that Slow Blood Clotting (Antiplatelet Drugs/ Anticoagulants)

Melatonin can slow the clotting of blood. Taking melatonin along with medications for slowing blood clotting can increase the risk of bleeding and bruising.

7. Nifedipine GITS

Nifedipine GITS is used for lowering blood pressure. The taking of melatonin supplements along with Nifedipine GITS can decrease its effects for helping to lower blood pressure.

8. Sedative Medications

Melatonin supplements can cause sleepiness and slowed breathing. Medications, known as sedatives, tend to cause sleepiness as well as slowed breathing. Sedative medications taken along with melatonin supplements can cause breathing problems and/or too much sleepiness.

9. Medications Changed by the Liver (CYP1A2 & CYP2C19)

The liver changes and breaks down some medications. Melatonin might change how quickly these medications are broken down by the liver. Unfortunately, this may change the effects and side effects of those medications.

10. Medications for High Blood Pressure (Antihypertensive Drugs)

Melatonin might lower blood pressure. Taking melatonin supplements along with medications for lowering blood pressure might cause blood pressure to drop too low. People taking melatonin supplements with these medications should closely monitor their blood pressure.

11. Medications for Preventing Seizures (Anticonvulsants)

Melatonin can increase the risk of seizures. So, taking melatonin supplements may decrease the effects of medications used to prevent seizures.

12. Medications with a Higher Chance of Getting a Seizure

Melatonin can also increase the rise of seizure in some people. There are also certain medications that may increase the risk of seizures. Taking both products together might increase the risk of a seizure further.

13. Methamphetamine (Desoxyn)

Taking melatonin supplements along with methamphetamine can increase the effects and side effects of methamphetamine.

14. Warfarin (Coumadin)

Warfarin is used for slowing blood clotting and melatonin might increase its effectiveness. Taking melatonin supplements along with warfarin might increase the chances of bleeding and bruising. Ensure that you have your blood checked on a regular basis if you’re taking melatonin supplements. Your dose of warfarin might also have to be changed.

Minor Interaction


Melatonin supplements have a minor interaction with the following substances, which is why you should be watchful when using them in combination.

15. Flumazenil (Romazicon)

The effects of melatonin can be decreased by flumazenil. Taking flumazenil along with melatonin supplements can decrease the effects of melatonin supplements.

16. Medications Changed by the Liver (CYP2D6) & CYP3A4)

The liver breaks down and changes certain medications. Melatonin can change how quickly the medications are broken down by the liver. This may change the effects and side effects of the medications.