The case for rapamycin as a longevity drug rests on mouse data. No human trial has shown that it extends life.
At Longevity Benchmark, we grade animal and human evidence separately. Rapamycin scores near the top for animal evidence, and near zero for human evidence. In mice, it worked across three laboratories. That's a meaningful result, but it's still a result in mice.
Rapamycin is a prescription immunosuppressant with a boxed warning. It's approved for kidney transplant patients and for one rare lung disease. No one has done the study that would tell us what a weekly dose does to a healthy 55-year-old over twenty years.
The Verdict
What Rapamycin Is and What It Is Approved to Treat
Rapamycin is sirolimus. It is a macrolide made by a soil bacterium collected on Rapa Nui and isolated in 1972. The name comes from the island.
Researchers pursued it as an antifungal until its effect on the immune system turned it into a transplant drug. The US Food and Drug Administration (FDA) label for Rapamune covers two indications. One is prophylaxis of organ rejection in kidney transplant patients aged 13 and older, and the other is lymphangioleiomyomatosis, a rare lung disease.
That label opens with a boxed warning about immunosuppression and says sirolimus is not recommended in liver or lung transplant patients. Two chemical relatives carry oncology approvals: everolimus, and sirolimus protein-bound particles, cleared in 2021 for a rare soft-tissue tumour. Ageing appears on none of them.
No regulator has approved any drug for ageing, anywhere. Ageing is not a recognised indication, so there is no endpoint a sponsor can register a trial against. Every longevity use of rapamycin is off-label by definition.
How Rapamycin Works on mTOR
Rapamycin inhibits mTOR, the mechanistic target of rapamycin, which is the sensor a cell uses to judge whether there is enough food to grow. When nutrients are plentiful, mTOR switches on protein synthesis and turns down the recycling machinery. Block it and the cell behaves as though food is short.
Autophagy rises, and damaged components get cleared. This is why rapamycin gets compared to caloric restriction. That overlap is why anyone tested the drug for lifespan at all. Our guide to a fasting protocol covers the dietary route to the same signal, which needs no prescription.
One further detail explains most of the dosing argument. Rapamycin acts fast on the first mTOR complex and slowly on the second. Work led by Dudley Lamming and published in Science in 2012 found that the insulin resistance rapamycin causes in mice tracks with losing that second complex. Weekly dosing is an attempt to hit the first and spare the second. That argument comes from mouse pharmacology. It is not evidence that weekly dosing is safe over decades.
What the Interventions Testing Program Found in Mice
The Interventions Testing Program (ITP) produced the strongest lifespan evidence available in any mammal, and rapamycin is its most reproducible positive result. The National Institute on Aging (NIA) funds it. Three independent laboratories test the same compound on identical protocols.
The mice are genetically varied rather than one inbred strain, and each cohort carries enough animals for 80% power to detect a 10% change in lifespan. That design matters because most single-laboratory lifespan claims do not survive replication. A compound can look life-extending when it has only made one mouse strain less prone to one disease, and an unlucky control group produces the same illusion.
The 2009 Nature paper reported that rapamycin extended median and maximal lifespan in male and female mice. Feeding began at 600 days of age, late middle age for a mouse, and it still worked. Based on age at 90% mortality, the increase was 14% in females and 9% in males.
Later cohorts tested other doses and starting ages, with effects that differ between the sexes. Read those percentages as mouse numbers. No arithmetic turns them into human years.
Why the Dog Aging Project Trial Matters More Than Another Mouse Study
TRIAD, the Test of Rapamycin In Aging Dogs, is the first rigorous test of a drug against biological ageing with lifespan as an endpoint outside a laboratory. Its published design is a parallel-group, double-masked, randomised, placebo-controlled, multicentre trial. Eligible dogs are healthy, at least seven years old, and inside the 20 to 50 kg weight band the trial sets.
Each dog takes rapamycin or placebo once a week for twelve months, then gets monitored for two further years. The whole study runs three years. Every dog comes back at six-month intervals for blood work. Dogs at cardiology sites also get an echocardiogram, and dogs at neurology sites get a neurological and cognitive assessment. Owners and assessing scientists stay blinded throughout.
A dog trial tells you more about people than another mouse study, for four reasons.
- Pet dogs live in human homes and share most of our environment.
- They develop age-related disease on their own, including heart disease, cancer, arthritis and cognitive decline, instead of carrying an engineered mutation.
- They are outbred, eat varied food, and live outside a temperature-controlled rack, so a result that survives that noise may survive ours.
- Their lifespan is short enough for TRIAD to run its course in three years, and nobody has run the equivalent trial in humans for exactly that reason.
Cognition and cardiac function sit in the secondary endpoints, so a healthspan answer should arrive before a lifespan answer does. A positive TRIAD result would make rapamycin the first drug with a lifespan effect in two mammals living in different conditions. A null result would push the mouse data back toward being a rodent finding.
Rapamycin Longevity Research, Ranked by What It Proves
Five bodies of evidence get cited in rapamycin longevity discussions, and they answer different questions.
| Study or dataset | Species | What it establishes | What it cannot tell you |
|---|---|---|---|
| Interventions Testing Program lifespan studies | Mice | Rapamycin lengthened median and maximal lifespan in both sexes at three laboratories, including when feeding began at 600 days of age | Nothing about people, and nothing about weekly tablets. These mice ate it in their chow continuously |
| TRIAD, the Test of Rapamycin In Aging Dogs | Companion dogs | A randomised, placebo-controlled test of lifespan and healthspan in animals living in ordinary homes | Nothing yet. Dogs are dosed for twelve months and monitored for two further years, so results are still years away |
| Everolimus vaccine-response trials | Adults over 65 | An mTOR inhibitor improved antibody response to influenza vaccine and lowered a marker of worn-out T cells | Whether a better vaccine response turns into a longer or healthier life |
| PEARL, the Participatory Evaluation of Aging with Rapamycin for Longevity | Adults aged 50 to 85 | Weekly compounded rapamycin over 48 weeks produced no more adverse events than placebo in 114 completers | Its primary outcome, visceral fat on a DXA scan, did not move. The benefits reported were secondary findings |
| Kidney transplant safety records | Transplant recipients | Decades of data on daily immunosuppressive dosing, including infection and malignancy rates | What weekly low-dose exposure does in a healthy person taking no other immunosuppressant |
The transplant row gets misread most often. Those records exist because transplant recipients take sirolimus daily, for years, alongside other immunosuppressants, while already unwell. They describe continuous immunosuppression well and say almost nothing about a single weekly dose in a healthy person.
What Rapamycin Longevity Trials in Humans Have Shown
The closest human evidence is about immune function rather than lifespan, and it used everolimus rather than rapamycin itself. A trial published in Science Translational Medicine in 2014 found that everolimus improved the antibody response to influenza vaccination in adults over 65. It also lowered the share of T cells carrying PD-1, a receptor that dampens T cell signalling and becomes more common with age.
A 2018 follow-up reported fewer infections in older adults on mTOR-pathway inhibition. The counterweight is rarely quoted alongside it. When the idea was scaled up, a phase 3 trial of 1,024 adults aged 65 and over tested the mTOR-pathway inhibitor RTB101.
It failed to beat placebo on clinically symptomatic respiratory illness, and the programme stopped. The small trials measured antibody titres. The large one counted illnesses.
PEARL is the closest thing to a rapamycin longevity trial in healthy people. It ran 48 weeks, randomised adults aged 50 to 85 to placebo or weekly compounded rapamycin at two dose levels, and had 114 completers. Its primary outcome was visceral fat measured by DXA, or dual-energy X-ray absorptiometry. It did not move.
Lean tissue mass and self-reported pain improved in women on the higher dose, and adverse events matched placebo. The authors list a small sample, a health-conscious volunteer group and self-reported adherence among the limits. Read it as a one-year safety signal.
Rapamycin Longevity Dosage and How People Get a Prescription
Sirolimus is prescription-only in the United States. Every longevity user is getting it off-label from a physician, which is lawful for a licensed clinician to do. The pattern those clinicians use is a single dose once a week, far below the daily maintenance dose the Rapamune label sets for transplant patients.
We are not going to print a milligram figure to copy, and the reason is not only caution. PEARL used compounded rapamycin, and its authors reported roughly one third the bioavailability of the commercial formulation. A dose lifted from a forum means nothing unless you also know which formulation it referred to.
Blood sirolimus levels vary widely between people taking the same tablet. Transplant medicine measures trough levels instead of trusting the milligram number, and a longevity prescriber may check yours. No completed trial has established the dose, the interval, or the long-term risk profile for healthy adults.
A competent prescriber gives you baseline bloods, a review interval, and a rule for stopping. A clinic selling a rapamycin protocol without booking those bloods is not managing the risk it just handed you.
Rapamycin for Longevity Side Effects and Monitoring
Mouth ulcers are the effect people report most often on weekly dosing, and the commonest reason someone cuts the dose or stops. Everything else below comes from the transplant label, where dosing is daily and continuous. Weekly users should expect less of it. How much less is unmeasured.
| Effect | What it looks like | What a prescriber monitors |
|---|---|---|
| Mouth ulcers | Sores inside the lip or cheek, often in the days after a dose | A direct question at each review, since ulcers are the commonest reason people cut the dose or stop |
| Impaired wound healing | Slower closure of surgical wounds and more wound complications | Pausing rapamycin around planned surgery or a dental extraction, on the prescriber’s timetable |
| Raised blood lipids | Higher total cholesterol and triglycerides, listed on the Rapamune label as a common reaction | A fasting lipid panel before the first dose and at intervals afterwards |
| Glucose changes | Higher fasting glucose and reduced insulin sensitivity | Fasting glucose and HbA1c, the marker that reports average blood sugar over about three months |
| Immunosuppression | Greater susceptibility to infection, plus the malignancy risk named in the label boxed warning | Full blood count, infection history, live-vaccine timing, and a review of every other immune-acting drug |
Impaired wound healing catches people out, because it turns an unrelated operation into a complication. Anyone with surgery or a dental extraction booked needs that conversation before the date. The immunosuppression risk is why the label carries a boxed warning, and why a prescriber asks about live vaccines and recent infections at every review.
Who Should Not Take Rapamycin for Longevity
Four groups should not start rapamycin.
- Anyone with an active infection.
- Anyone already taking an immune-suppressing drug.
- Anyone pregnant or trying to conceive.
- Anyone with surgery or a dental extraction in the diary.
The Rapamune label backs all four. Immunosuppression raises infection risk, wound healing slows and grows more complicated, and animal data show fetal harm.
The larger group rapamycin does not serve is people whose real goal is a better biological age result. No trial shows that rapamycin lowers an epigenetic age score. The things that reliably move those numbers are cheaper, need no prescription, and carry no boxed warning, and our guide on how to lower biological age ranks them.
For a compound with real evidence and an ordinary safety profile, creatine is a better first purchase than a prescription immunosuppressant. Human trials of the nicotinamide adenine dinucleotide (NAD) precursors report blood NAD levels rather than any clinical outcome. Their tolerability is documented far better than rapamycin's, as our page on NMN side effects sets out.
Anyone weighing rapamycin against metformin should read our rapamycin vs metformin comparison. Readers drawn here by the mTOR mechanism will find the same reasoning applied to senolytics, which sit a tier further back again.
What Would Change Our Answer on Rapamycin for Longevity
One thing would flip this verdict: a completed randomised controlled trial in healthy older adults with a hard clinical endpoint. That means several thousand people, several years, and a count of deaths or new age-related diagnoses. A biomarker will not do.
No such trial is under way, and funding one is hard precisely because ageing is not an approvable indication. A positive TRIAD result would move us a long way without getting us there. It would justify the human trial nobody has funded, and dogs are still not people.
Until one of those lands, the useful next step is not a purchase. If rapamycin for longevity interests you, take the Nature paper and the Rapamune label to a physician, and ask for baseline bloods and a plain account of what is unknown. In the meantime, spend the effort on the levers in our supplements guides that already have human trials behind them.
Frequently Asked Questions
Is rapamycin a longevity drug?
It is a prescription immunosuppressant that extends lifespan in mice, which is not the same thing. The US Food and Drug Administration approves it to prevent organ rejection after a kidney transplant and to treat lymphangioleiomyomatosis, a rare lung disease. No regulator anywhere has approved a drug for ageing. The mouse data is the reason people call rapamycin a longevity drug. It is not the only mouse lifespan result now being read that way: a Nature study started semaglutide in 20-month-old mice and reported a median lifespan close to 100 days longer, with the same species gap behind it.
Does rapamycin increase longevity in humans?
No human trial has shown that rapamycin extends human lifespan, and none is running. The human studies that exist are short and use surrogate endpoints such as vaccine response, body composition and self-reported quality of life. The largest of them, PEARL, ran 48 weeks in 114 people and missed its primary outcome. Anyone quoting a human lifespan figure for rapamycin is quoting a mouse.
How much does rapamycin extend life in mice?
The 2009 Nature report from the Interventions Testing Program gives the cleanest figure. Rapamycin started at 600 days of age raised the age at 90% mortality by 14% in females and 9% in males. Those mice ate it continuously in their food. No arithmetic converts that into human years.
How do you get rapamycin for longevity?
Only through an off-label prescription from a physician, because sirolimus is prescription-only in the United States. Prescribing an approved drug outside its labelled indication is lawful for a licensed clinician, and some longevity practices do it openly. Expect baseline bloods, an agreed review interval, and a question about mouth ulcers and infections at every visit. Sirolimus bought without a prescription is unverified in identity, dose and purity.
Is rapamycin FDA approved?
Yes, but not for ageing. The Rapamune label covers prophylaxis of organ rejection in kidney transplant patients aged 13 and older, and the treatment of lymphangioleiomyomatosis. Two related mTOR inhibitors carry oncology approvals, everolimus and sirolimus protein-bound particles. Longevity use sits outside all of those labels, which is what off-label means.
What are the side effects of rapamycin at longevity doses?
Mouth ulcers are what people report most often on weekly dosing. The Rapamune label reflects daily transplant dosing and adds diarrhoea, abdominal pain, nausea, acne, peripheral oedema, headache and raised cholesterol. It also carries a boxed warning covering immunosuppression, infection and malignancy. Impaired wound healing matters if you have surgery booked, and no completed trial has measured how much a weekly dose softens any of this.
What is the rapamycin dog longevity study?
TRIAD, the Test of Rapamycin In Aging Dogs, run by the Dog Aging Project. It is a randomised, double-masked, placebo-controlled, multicentre trial in healthy pet dogs that are at least seven years old and between 20 and 50 kg. Dogs take rapamycin or placebo once a week for twelve months, then get monitored for two further years. Check-ups fall every six months, and survival time is the primary endpoint.
Is sirolimus the same as rapamycin?
Yes. Sirolimus is the generic name and rapamycin was the original laboratory name, so sirolimus and longevity discussions cover the same molecule. Rapamune is the brand name for the tablet and oral solution. Everolimus is a chemically modified relative with its own approvals, and it is the drug used in the older-adult vaccine trials people cite as human rapamycin evidence.