Melatonin is best known as the hormone that regulates sleep, but new research suggests it may also help reduce muscle and joint pain. While it is widely used to treat insomnia and jet lag, scientists now believe melatonin could have additional benefits by easing chronic pain and improving sleep quality.
Produced naturally by the pineal gland in the brain during the night, melatonin helps regulate the body’s sleep-wake cycle. Because sleep and pain are closely connected—poor sleep can worsen pain, while pain can disrupt sleep—researchers have long been interested in understanding whether melatonin could influence pain directly.
Scientists believe melatonin may reduce pain by dampening pain signals in the brain and spinal cord, lowering inflammation, calming overactive nerves and protecting cells from oxidative stress, a process caused by the buildup of harmful molecules that damage tissues over time.
The latest study combined data from 23 clinical trials involving more than 2,000 participants to assess melatonin’s effectiveness in treating long-term muscle and joint pain as well as pain after surgery.
The analysis found that melatonin provided modest improvements for people suffering from chronic muscle and joint pain. On average, participants reported a reduction of about nine points on a 100-point pain scale, while many also experienced better sleep. Researchers noted that this level of pain relief is comparable to that reported for some anti-inflammatory medicines in separate studies, although no direct comparison has been made.
However, the researchers also highlighted that melatonin’s effectiveness may depend on whether patients already experience sleep problems or have other long-term health conditions. Most participants in the chronic pain studies already suffered from poor sleep, but none of the trials separately analysed outcomes for people with and without sleep disorders. As a result, it remains unclear whether melatonin works better for individuals who struggle with sleep.
The findings were far less encouraging for post-surgical pain. Melatonin showed little to no meaningful improvement in either pain or sleep after surgery. One analysis reported a very small reduction of about 2.5 points on a 100-point pain scale, a difference considered too small to be clinically significant for recovering patients.
Researchers emphasised that melatonin should not be viewed as a replacement for established treatments. Instead, it may serve as an additional therapy alongside physiotherapy, regular exercise and anti-inflammatory medications for managing chronic muscle and joint pain.
The review also identified several unanswered questions. The clinical trials used a wide range of doses, varying from 1 mg to 10 mg, making it difficult to determine the most effective dosage. Some evidence suggested that longer treatment durations may produce better results for chronic pain, but this conclusion was based on only a limited number of studies.
Although higher doses appear safe in other research, there is still insufficient evidence to recommend them specifically for pain management.
Melatonin is generally considered safe for short-term use, but it can cause side effects such as daytime drowsiness, dizziness, headaches and nausea. People with liver or kidney disease, as well as those living with autoimmune conditions such as rheumatoid arthritis, are advised to consult a doctor or pharmacist before using melatonin supplements.
Regulation of melatonin also varies widely across countries. In the United States, it is available over the counter as a dietary supplement and can be purchased without a prescription. In contrast, the United Kingdom classifies melatonin as a prescription-only medicine, approved primarily for the short-term treatment of sleep disorders and jet lag.
While the latest findings suggest melatonin may offer modest benefits for chronic muscle and joint pain, researchers say larger and more detailed studies are needed before it can be recommended as a routine treatment for pain management.