Melatonin's Role in Sleep and Pain: What Science Says
Translated & summarized from Ynet by baba
A new study suggests melatonin may offer slight relief for chronic pain and improve sleep quality, but its effectiveness as a painkiller is not clinically significant. In Israel, melatonin is a prescription drug primarily for short-term insomnia treatment in older adults, with its use for pain considered off-label.
The story in 5 lines · by baba
- Melatonin shows modest pain relief and better sleep quality in chronic pain patients.
- Its primary function is regulating the body clock, not acting as a sedative.
- Evidence supports melatonin for jet lag and specific insomnia cases, not healthy individuals.
- In Israel, melatonin is a prescription drug, unlike in the US where it's a supplement.
- Timing of intake and dosage are crucial; higher doses aren't always better.
A recent systematic review and meta-analysis published in the journal PAIN explored the effects of melatonin, a hormone naturally produced by the body in response to darkness, on chronic pain and sleep quality. The study, which included 23 randomized controlled trials with 2,028 adult participants, found a modest reduction in chronic musculoskeletal pain, averaging 8.96 points on a 0-100 scale, which fell below the threshold for clinical significance. However, a more consistent finding was an 11.35-point improvement in sleep quality among patients with chronic pain.
While these findings do not position melatonin as a pain reliever, they highlight its potential and prompt a clearer understanding of its function. Melatonin is not a sedative like benzodiazepines; its primary role is to regulate the body's internal clock, signaling the onset of night. Professor Moti Chaimi, a district pediatrician, emphasizes that the timing of melatonin intake can be as crucial as the dosage, as incorrect timing may disrupt the biological clock and worsen sleep disturbances.
Evidence for melatonin's efficacy is strongest for circadian rhythm disorders, such as jet lag and delayed sleep phase syndrome. It is also recommended for insomnia in children on the autism spectrum and shows moderate evidence for primary insomnia in individuals aged 55 and older, where it can shorten sleep onset by about ten minutes. However, there is insufficient evidence to support its use in healthy individuals or for conditions like anxiety and chronic pain, immune system regulation, or anti-aging.
In Israel, unlike the United States where it's sold as a dietary supplement, melatonin is a prescription medication. The approved Israeli product, Circadin (2mg extended-release), is intended for short-term treatment of primary insomnia in those over 55. Its use for pain is considered off-label. Professor Chaimi advises caution, particularly for pregnant or breastfeeding women, individuals with autoimmune diseases, epilepsy, or liver dysfunction, and stresses that use in children requires medical supervision.
Regarding dosage, higher amounts do not necessarily equate to better results. Even small doses can significantly elevate melatonin levels. Higher doses may prolong the effect and increase morning grogginess or headaches without necessarily improving sleep. Common side effects include headaches, dizziness, nausea, and morning drowsiness. While not considered addictive, long-term use data is limited, with most studies lasting only weeks to three months. Concerns exist regarding imported melatonin supplements due to potential inconsistencies in actual content versus labeled dosage and a preliminary observational study suggesting a link between long-term use and increased risk of heart failure, hospitalization, and mortality, though causality is not established.