WEDNESDAY, July 1, 2026 (HealthDay News) — The sleep supplement melatonin might also be useful in treating chronic pain, a new evidence review says.

Melatonin appears to reduce chronic muscle and joint pain as much as painkillers like opioids, aspirin, Aleve (naproxen) and Tylenol (acetaminophen), researchers reported June 30 in the journal Pain.

“Melatonin is already in people’s homes, it’s inexpensive, and we know it’s safe,” lead researcher Kangchao Wu, a doctoral student at the University of Sydney in Australia, said in a news release.

“What’s exciting is that melatonin may also help manage chronic pain, opening the door to reducing reliance on medications that come with more risks,” Wu said.

For the new study, researchers analyzed data from more than 2,000 people participating in 23 randomized controlled clinical trials around the world.

The participants had conditions like low back pain, wear-and-tear arthritis and fibromyalgia, or were recovering from surgeries like joint replacements and spinal repairs.

On average, melatonin reduced pain by up to 10 points on a 0-to-100 scale, results showed. That’s a magnitude similar to widely used pain medications, researchers said.

The supplement also improved people’s sleep, researchers found.

“For many patients, pain doesn’t exist in isolation and is closely tied to poor sleep,” Wu said. “Melatonin appears to target both, which makes it particularly useful for people managing chronic pain.”

These results highlight the growing potential of drug repurposing — using existing treatments in new ways, said researcher Paulo Ferreira, director of the Musculoskeletal Research Hub at the University of Sydney.

“We’re taking a medication we already understand and applying it to a problem that affects a huge proportion of the global population,” Ferreira said.

Across the trials, the dose and timing of melatonin varied depending on a person’s condition.

For chronic pain, doses typically ranged from 3 to 10 milligrams (mg), with 3 mg per day most commonly used.

For pain following an operation, doses ranged from 1 to 10 mg, with 5 to 6 mg the most common.

The researchers did not find evidence of a clear dose-response relationship, meaning no “best” dose can be gleaned from the current data.

Larger-scale studies are needed to confirm and better understand melatonin’s pain-relieving potential, researchers said.

However, anyone thinking of using melatonin as a painkiller should talk it over with their doctor, researchers said.

“Our advice isn’t for melatonin to replace every pain medication,” Wu said. “Instead, after consultation with a doctor, it may be used as an adjunct to existing treatments, particularly for people who also experience sleep problems.”

He said the level of pain relief observed was comparable to some conventional treatments.

“But this does not mean melatonin should replace them,” Wu said. “Rather, it may offer a safer additional option within a broader pain management plan.”

More information

The Mayo Clinic has more on melatonin.

SOURCE: University of Sydney, news release, June 30, 2026