What is melatonin?
Melatonin is a hormone produced naturally in the body that is involved in the regulation of the day-night rhythm. It is also colloquially referred to as the “sleep hormone”. However, it not only influences sleep, but also has other functions in the body.
Formation of melatonin in the body
Naturally, the body produces melatonin mainly in the pineal gland of the brain (pineal gland). However, small amounts are also produced by the retina of the eye and the intestine.
What influences melatonin levels
The body’s production of melatonin naturally decreases with age. However, a low melatonin level or melatonin deficiency can also be caused by excessive consumption of caffeinated beverages, alcohol or nicotine. Sporting activity in the evening as well as permanent stress also lower the melatonin level. Another (very) rare cause is a deficiency of the nerve messenger serotonin.
Conversely, a (permanently) elevated melatonin level can be the result of long periods of darkness in the winter months with few hours of sunlight. This effect may be involved in the phenomenon of the “winter blues” or “winter depression,” experts suspect.
Certain antidepressants and liver dysfunction can also increase the amount of melatonin in the body.
What melatonin preparations are available?
Sleep disorders in people aged 55 and older: To improve poor sleep quality, a doctor may prescribe melatonin if the sleep disorder has no physical or psychiatric cause (primary insomnia). The application is only short-term.
Jet lag: In Germany (but not in Austria and Switzerland), a prescription-only melatonin drug is also approved for the short-term treatment of jet lag in adults. Since March 2022, it has been classified as a lifestyle drug and is therefore no longer reimbursable.
According to studies, externally applied melatonin can help with hair loss (alopecia), for example in the case of congenital or diffuse hair loss in women.
How is melatonin used?
How many milligrams (mg) of melatonin can be taken per day and exactly how it is used depends on the intended use.
Sleep disorders from the age of 55
Affected people take a melatonin tablet in the evening to fall asleep, after the last meal and one to two hours before bedtime. The tablet must be swallowed whole. If it is crushed or chewed, it loses its retard properties!
Sleep disorders in autism and/or Smith-Magenis syndrome.
The melatonin preparation for minors with autism and/or Smith-Magenis syndrome also contains sustained-release tablets. Two dosages are available: one and five milligrams.
It is usually started with two milligrams. If that does not sufficiently help with the sleep disturbances, the treating physician can increase the melatonin dose to five milligrams. The maximum daily dose is ten milligrams.
With regard to the duration of treatment, there are so far data on melatonin intake over a period of up to two years. After at least three months of use, the attending physician will assess whether the drug is actually helping the minor patient sleep. If so, the physician will periodically assess whether continued use is still necessary.
Jet lag
If the usual dosage of three milligrams does not sufficiently alleviate jet lag symptoms, you can try the higher-dose preparation (tablets of five milligrams of melatonin each).
One should not eat for two hours before and after taking it. People with elevated blood sugar levels or diabetes should ideally take the melatonin preparation no earlier than three hours after eating.
Use of over-the-counter melatonin preparations
Caution: Anyone who is hypersensitive to melatonin must not take corresponding preparations (prescription or over-the-counter). The same applies to an existing hypersensitivity to other ingredients.
What are the side effects of melatonin?
In general, melatonin preparations are quite well tolerated. However, harmful effects in the sense of side effects are still possible. The preparations should therefore not be taken without hesitation.
Menopausal symptoms and weight gain are also occasional side effects of melatonin. The same applies to increased blood pressure, nightmares, anxiety, insomnia, irritability, nervousness and restlessness.
Rarely, these melatonin medications trigger, for example, depression, aggression, increased sexual desire, prostatitis, memory and attention problems, blurred vision, or dizziness.
Short-term use of melatonin preparation for jet lag may cause headache, nausea, loss of appetite, drowsiness, daytime sleepiness, and disorientation, according to the professional information.
Is melatonin addictive?
The body can become accustomed to many prescription sleeping pills, but not to taking melatonin. There is no risk of addiction here.
Overdose or wrong time of intake
In addition, too high a dose of melatonin can really upset the sleep-wake rhythm – as can taking it at the wrong time. If you take the melatonin medication in the middle of the night, for example, you may still feel the sleep-promoting effect the following morning. This can be dangerous if, for example, you are driving in the morning.
How does melatonin work?
In addition, melatonin has an effect on the thyroid gland: the production of thyroid hormones is inhibited. This slows down the metabolism, lowers energy consumption, reduces body temperature and influences the release of sex hormones.
Benefits of taking melatonin
Taking melatonin preparations as a sleeping pill or sleep aid is supposed to normalize a disturbed day-night rhythm, shorten the time it takes to fall asleep and even improve sleep. But is this really true?
The melatonin drugs approved in Germany, Austria and Switzerland are each intended for a specific area of application and a specific patient group. For this precisely defined purpose, their efficacy could be proven in studies – one of the prerequisites for approval as a drug.
Manufacturers of dietary supplements containing melatonin are not required to submit studies on the efficacy of their preparation before they are allowed to market it.
Sleep disorders often disappear on their own when the trigger (such as stress) is removed and good sleep hygiene is maintained (e.g. regular bedtimes). If not, you should have them checked out by a doctor. This is especially true for children with sleep disorders.
These interactions can occur with melatonin
Here is an overview of agents that should not be taken simultaneously with melatonin, and only with caution:
- Fluvoxamine and imipramine (antidepressants)
- Benzodiazepines (sleeping pills such as diazepam and lorazepam)
- Z-drugs (sleeping pills such as zolpidem and zopiclone)
- thioridazine (used to treat psychosis)
- Methoxypsoralen (used for phototherapy in psoriasis)
- cimetidine (heartburn medicine)
- Estrogens (e.g., in hormonal contraceptives or hormone replacement products)
- Rifampicin (antibiotic)
- Carbamazepine (drug for epilepsy)
In addition, you should not combine the intake of melatonin with alcohol. Beer, wine & Co. can reduce the effectiveness of melatonin on sleep.
This list is only a selection. Interactions with other active ingredients (at least) are also conceivable. Therefore, ideally consult your doctor before taking melatonin preparations.
Melatonin during pregnancy and breastfeeding
Natural melatonin can pass into breast milk. This probably also applies to externally supplied melatonin. The hormone can enter the baby’s body via breast milk. The possible effects are not yet known. As a precaution, experts advise against taking melatonin and breastfeeding at the same time.