Here’s why a longevity researcher takes rapamycin for joint pain

• Rapamycin is a prescription drug that has anti-aging effects on mice and flies.
• Matt Kaeberlein is studying rapamycin, and he decided to use it to try to cure a frozen shoulder.
• Although it has helped, we don’t yet know the risks or benefits of using this drug for anti-aging in humans.

A few years ago, Matt Kaeberlein, director of the University of Washington’s Healthy Aging and Longevity Research Institute, began to suffer from the excruciating pain of a frozen shoulder. He says he had trouble sleeping, felt “nervous and depressed” and “couldn’t go throw a ball” with his child like he used to.

Kaeberlein – 49 at the time – had a guess about what was wrong with his body. “I got to thinking, this is an age-related inflammatory disease,” he told Insider. This idea led him to a possible solution: a little-known drug called rapamycin.

At work, Kaeberlein studies how the drug, an immunosuppressive agent typically prescribed to organ transplant recipients and cancer patients, can help people age more gracefully – keeping muscles pain-free, brains sharp, even in fighting viruses.

So Kaeberlein tried rapamycin on himself, in what he admits was a loosely controlled “self-experiment” to cure his shoulder.

What he went through for about 2.5 months taking rapamycin every week “made me believe” in the drug, he said. “I would say 90% of the range of motion was back and the pain was probably 90% gone – and it hasn’t returned.”

Now he takes rapamycin, which costs about $1 a pill, on a cyclical schedule, dosing in 10-12 week increments every six to eight months or so in hopes of warding off inflammation related to the ‘age.

Rapamycin has been shown to slow aging in flies, worms and mice

To date, Kaeberlein has tracked how more than 330 people taking rapamycin feel about taking the off-label drug to try to fight aging. Many say they feel great, with less stomach pain and less anxiety than their peers.

It’s possible that rapamycin may have anti-aging effects, reducing age-related inflammation issues as diverse as dementia, cancer, or simple muscle pain. But we don’t know for sure.

In mice, the assessment of rapamycin is more proven. The antifungal compound – first discovered in a clod of earth on the remote island of Rapa Nui, or Easter Island – is a well-known life extender for flies, worms and mice. It targets a key protein in the body that regulates and promotes cell reproduction, slowing it down and discouraging growth, much like fasting.

“Rapamycin is quite effective — in mice — at eliminating age-related inflammation,” Kaeberlein told Insider.

We don’t know the risks of taking rapamycin for aging — or the best dosage for people

Although Kaeberlein’s personal experience was successful, he told Insider that at this time we cannot say how beneficial or risky rapamycin may be when taken in small doses to combat the aging of our cells.

Its data suggests that one of the most common side effects among users is quite mild: canker sores in the mouth.

But no one has yet developed a clear protocol on how to take rapamycin as an anti-aging drug. Kaeberlein has developed his own rapamycin routine based on what happens in lab mice.

“Honestly, I don’t have a good rationale — I kind of try different things,” he said.

Other biohackers take the drug more regularly, taking it once a week, simply because a 2014 Novartis study suggested that might be a better strategy than daily.

Longevity experts emphasize that anyone taking rapamycin should be under the strict supervision of a doctor. Because if rapamycin can boost the immunity of older people against viral illnesses like the flu – and could maybe have a similar effect on COVID – it could also impair certain aspects of immune function and make people more susceptible to bacterial infections.

Kaeberlein says that for now, her favorite proven tips for aging well are still the ones you’ve heard many times before: eat a balanced diet, exercise and sleep well.

“If you had to pick one thing that’s probably best,” he said, “at least for functional aging, it’s exercise.”