Rapamycin (sirolimus)

Read the research

• Rapamycin vs metformin for dogs and cats: two longevity drugs, one has the pet evidence

  Both are borrowed from human medicine and floated for pet ageing. Only one has a randomized trial in dogs and robust lifespan data in mammals — and it isn't the cheap, familiar one.

• Rapamycin alternatives for aging dogs and cats: what's actually claimed, and what has evidence

  If rapamycin isn't right for your animal, several supplements and one serious drug programme are sold as alternatives. Here's an honest ranking of what the evidence supports — and where it runs out.

• Rapamycin side effects in dogs and cats: what the trials actually reported

  At the low, intermittent doses used in pet trials, serious adverse effects were uncommon and mostly mild. But rapamycin is an immunosuppressant, the long-term pet data doesn't exist yet, and some animals should never take it.

• How to get rapamycin for a dog or cat — the legitimate routes, step by step

  It is a prescription drug, so there is no route that skips a veterinarian. Here is how the process actually works, what to ask, and how to tell a careful provider from a careless one.

• Rapamycin dosage for dogs and cats: what the trials used, and why we won't give you a number

  This is one of the most-searched questions in pet longevity, and the honest answer is uncomfortable: the dose is not a number you should take from a website — including this one.

• The ageing dog's heart — and the one place a rapamycin trial actually saw something

  Heart function is where the canine rapamycin data is least thin. It is also one small study over ten weeks. Here's what happens to an old dog's heart, what to watch for, and how much that finding really carries.

• Dog arthritis: what actually helps, and where rapamycin fits (it doesn't, yet)

  Osteoarthritis is one of the most common — and most under-treated — conditions in older dogs, largely because dogs hide pain so well. Here is what has real evidence behind it, and an honest look at the rapamycin claim.

• Old dog, confused at night: canine cognitive dysfunction explained

  Pacing at 3am, staring at walls, forgetting the door they've used for years. Canine Cognitive Dysfunction is common in old dogs, frequently mistaken for ordinary ageing — and several of the things that mimic it are treatable.

• Cancer in dogs: the real risk, the prevention claims, and what evidence supports

  Cancer is a leading cause of death in older dogs, which makes it the area where hopeful claims spread fastest. Here is what actually lowers risk or catches it early — and an honest look at whether rapamycin belongs in that list.

• Feline stomatitis: one of the most painful diseases in cats, and why rapamycin isn't the answer

  Chronic gingivostomatitis leaves a cat with a mouth too sore to eat. It is genuinely awful, genuinely treatable, and a magnet for immune-modulation claims that have never been tested in cats.

• Is rapamycin an immunosuppressant? The dose question everyone gets wrong

  It is the sentence used to end every conversation about rapamycin — and it is true, at one dose, and close to backwards at another. Here is the distinction that decides everything.

• Rapamycin and the feline kidney: the study everyone hopes exists, and what actually happened

  Kidney disease is the thing most likely to take an old cat, so it is where hope runs hardest. Here is the honest state of the evidence on mTOR inhibitors and the kidney — including the human trials that disappointed.

• Why big dogs die young

  Across species, bigger animals live longer. Within the dog, it flips: a Great Dane is old at six while a terrier is barely middle-aged. The reason runs straight through the pathway the whole longevity field is built on.

• The Dog Aging Project and TRIAD: what we will learn, and when

  The largest study of ageing in pet dogs ever run, and the trial inside it that could show a drug extends canine lifespan. What each one is actually testing — and why the honest answer today is “we don't know yet.”

• Your cat has a heart murmur. Here is the only rapamycin trial ever run in cats.

  Hypertrophic cardiomyopathy is the most common heart disease in cats, it usually arrives without symptoms, and it is the one place where feline geroscience has actually been tested. What the evidence supports — and what it does not.

• Rapamycin: the most-studied longevity drug in biology, and what it means for dogs and cats

  It extended lifespan in mice from three independent labs. It has a randomized trial in pet dogs. It is also a prescription immunosuppressant that people keep describing carelessly. Here is what the evidence actually says.

• The longevity compounds, and how strong the evidence really is

  An honest, compound-by-compound map of the pet-longevity literature — with a graded evidence badge and primary-source citations for every molecule, including the ones that disappoint.