It may seem like a magical solution for a peaceful night. A fruit-flavored gummy, a couple of drops in a glass of water, and suddenly, the child falls asleep. However, what is sold in pharmacies under an aura of 'natural supplement' is actually a potent hormone: melatonin.
The data presented at the XXXIV Annual Meeting of the Spanish Sleep Society (SES) last week in Granada is an important warning. A study based on surveys of 829 families (308 in a hospital setting and 521 through social media) concludes that 33% of Spanish families give melatonin to their children solely based on advice from a family member, a friend, or what they have read on social media or an internet forum. The percentage rises to 41% in families who responded to the questionnaire through social media.
"I would focus more on the surveyed population in a hospital environment, where up to 20% admit to having started melatonin treatment based on advice from friends, family, or social networks, despite having relatively frequent contact with their child's doctors," reflects Elena Martínez-Cayuelas, the lead author of the research.
The study also shows that the majority of families (54%) continue melatonin treatment for months or even years, without medical follow-up (69%), and in this aspect, the false sense of security conveyed by melatonin, not classified as a drug, can have a significant influence, suggests Martínez-Cayuelas. In fact, the survey reveals that 77.8% of families perceive melatonin as safe, 40% consider it a "natural treatment," and the majority (80%) admitted ignorance of possible side effects.
Melatonin Side Effects
Martínez-Cayuelas points out that the profile of melatonin side effects is good. "Most of the time we do not find any or they are very subtle: a bit of headache, some daytime drowsiness, enuresis (bedwetting)... The problem arises from chronic long-term use. There are increasing high-quality studies on forms considered treatment (above 2 milligrams), which are marketed as drugs and require a prescription, informing us of long-term effects. However, many families treat their little ones with melatonin for years, and there is a knowledge gap there."
Should Be Considered a Drug
The study author emphasizes that personally, "I don't like the word natural. It implies a sense of harmlessness, that it does no harm, but it is a hormone and should be considered as just another drug, meaning it should not be freely sold under the guise of a supplement just because it contains less than 2 milligrams of melatonin [those with more than 2 mg are marketed as drugs and have trials on them]. Regulating the drug would be ideal in Pediatrics."
In this regard, some progress has been made. Data indicates that melatonin use in developed countries has been skyrocketing in the last decade without medical supervision or public awareness of consuming a hormone, as it is marketed as a dietary supplement. In 2022, the Pediatric Working Group of the SES led a document, published with four of the main pediatric scientific societies -the Spanish Association of Pediatrics (AEP), the Spanish Society of Extrahospital and Primary Care Pediatrics (Sepeap), the Spanish Association of Primary Care Pediatrics (Aepap), and the Spanish Society of Pediatric Neurology (Senep)-, expressing "deep concern" about the free commercialization of melatonin preparations as dietary supplements, as well as their use and abuse in the pediatric population "without the need for medical indication or supervision."
At that time, a letter was sent to the Director General of Public Health and the Director General of the Common Portfolio of SNS Services and Pharmacy outlining their opinion on melatonin, requesting restrictions on free dispensing in formats tailored to the pediatric population and increased quality and composition controls of those products.
This lack of medical oversight causes families to lower their guard. As Marta Castell, a pediatrician at the Campanar Health Center (Valencia) and coordinator of the Gastroenterology, Endocrinology, and Nutrition working group of the Aepap, points out, the term "supplement" has a paradoxical effect: "It seems to supplement what is lacking, in the case of melatonin only if there is inadequate natural secretion of that hormone. In reality, we are medicalizing a process that could be solved with sleep routines and habits (for example, avoiding screens a couple of hours before bedtime)." She also notes that selling it without a prescription or medical supervision, "in gummy or candy form, can lead to the belief that it is harmless. There is also a risk of accidental massive intake by the child or certain psychological dependence on 'if I don't take a candy or gummy, I can't fall asleep'."
Chemical darkness
Melatonin is a natural hormone produced by the body, synthesized to regulate sleep in the early afternoon and induce sleep, meaning it helps regulate our circadian rhythms of wakefulness and sleep, regulating the biological clock.
"The most influential factor in that secretion is the light-dark cycle, and taking melatonin exogenously is like setting our clocks, resynchronizing. It is true that this chronoregulatory effect is beneficial, and often the treatment is given for a few weeks, then stopped, and we are adjusted to that new schedule we were seeking. But there are no high-quality clinical trials or reviews regarding treatment in Pediatrics, and it is not just about the hormone that aids in sleep, it is the hormone of chemical darkness: it tells all our organs that it is night, the pancreas, the liver, etc., will act as if it were night, with a different function. Essentially, we are giving contradictory information to the body, a different synchronization, and there is a significant research gap there," assures Martínez-Cayuelas.
In the case of children, we are playing with their neurodevelopment, when most sleep problems can be improved and treated without any medication. Castell draws a parallel: "It's like someone starts taking Ozempic without even thinking about changing their diet or exercising, you have to start from the beginning. Specialists believe that you have to understand children's sleep and be vigilant about environmental changes. "We can't expect a baby under 6 months, even under 2 years, to sleep through the night. It is also part of normal brain maturation and how sleep is structured in the first two years. You always have to rule out organic pathology and see what is happening with that child because there are diseases related to sleep disorders and others that are simply a variant of normality. From 2 to 6 years old, there are moments when there are nightmares, sleepwalking begins, and these are variations of normality that often disappear on their own."
And then the child matures and goes from daycare to school, makes changes in the school routine or returns from holidays, the pediatrician indicates, "important events that can disrupt sleep, and that does not mean there is an underlying disease. We have to see how the family is: if a grandparent is missing, if there is a separation or divorce process... Imagine being a child of 5 or 6 years old and suddenly you have two homes, two beds to sleep in with two different sleep routines that change every week. That disrupts sleep, and the problem is not the child, so sometimes there are setbacks and frequent awakenings again, for example."
Martínez-Cayuelas acknowledges that sleep problems in children are difficult for families to manage, but they tend to resolve on their own as the child gets older. It's important to always discuss it with doctors to understand the underlying cause or if there might be a real problem. "In children with neurodivergent conditions, such as autism spectrum disorder or attention deficit hyperactivity disorder, sleep problems often persist and become chronic. In these cases, it's very common for us to have to use melatonin," adds the neuropediatrician.
This is also true for children with severe visual impairments who don't receive light stimulation. But in all cases, it should be done following a doctor's instructions and monitoring, not because it worked for a parent in the school's WhatsApp group.
Shared Responsibility
The study's data is worrying for Martínez-Cayuelas because it may indicate that doctors don't have sufficient tools to detect the sleep problems that concern families. "It's a self-critique to consider what we can do to improve the situation where families who have access to medical care haven't sought help, or perhaps the doctor didn't ask the questions in the right way. We need to see how we can improve the dissemination of knowledge about sleep. It's true that in this respect, I think it's mainly a lack of time. Often, when you have to address a thousand problems in a consultation, it's complicated."
Castell agrees: "We lack time in consultations. You can't do a sleep consultation in 7 or 10 minutes, it's impossible. The same goes for consultations about obesity and ADHD. Families come to the appointment asking for a check-up or a vaccination, forgetting to ask about sleep. It's a problem they keep putting off until they can't anymore, and often, if the doctor isn't readily available, or if there's no accessibility or time, they look for alternatives elsewhere. In the end, parents look for solutions wherever they can, and if the solution is on a GPT chat, the internet, Dr. Google, or Amazon, then that's where they go. These days, they have access to a huge amount of information, more than 20 years ago, but there's a chaos of data, and it's often contradictory. So, we all have to work together because it's a multifactorial issue."