Rapamycin

Medically reviewed by Dr. Sarah Mitchell, RPh, Clinical Pharmacist — Updated January 2026

What Is Rapamycin (Sirolimus)? — Two Distinct Canadian Audiences

Rapamycin reaches drugs-canada.com from two completely different groups of Canadian users, with different goals, different dosing protocols, and different medical contexts:

Audience 1 — Transplant patients and oncology: Canadians prescribed sirolimus by their transplant nephrologist or oncologist for prevention of organ rejection after renal transplantation, or for treatment of certain cancers (renal cell carcinoma, lymphangioleiomyomatosis). This is the Health Canada-approved indication. These patients typically take 2–5 mg daily under close medical supervision with therapeutic drug monitoring (target trough levels 4–12 ng/mL).

Audience 2 — Longevity / anti-aging off-label: Canadian adults seeking to harness rapamycin's mTORC1-inhibiting properties for healthy aging, senolytic effects, and lifespan extension based on the growing body of mammalian research. This population typically takes much lower intermittent doses (2–6 mg once weekly) without the immunosuppression that accompanies continuous high-dose transplant protocols. This is off-label use — not approved by Health Canada for this indication.

The mTOR Pathway — Why Rapamycin Is Different From Every Other Drug

mTOR (mechanistic Target Of Rapamycin) is a serine/threonine kinase that functions as the master regulator of cellular metabolism, growth, and aging. It integrates signals from nutrients, growth factors, energy status, and stress to determine whether a cell should grow, divide, produce proteins, or activate autophagy (cellular self-cleaning). Understanding mTOR is essential for understanding why rapamycin has attracted such extraordinary scientific interest as a potential longevity drug.

mTOR exists in two distinct complexes with different functions:

mTORC1 (rapamycin-sensitive complex): The primary target of rapamycin. mTORC1 promotes anabolic processes — protein synthesis, cell growth, lipid synthesis — and suppresses autophagy and lysosomal biogenesis. Chronically elevated mTORC1 signalling (driven by excess nutrients, growth factors, and aging) is associated with accelerated cellular senescence, reduced autophagy, accumulation of damaged proteins and organelles, and shortened lifespan across virtually every model organism studied. Inhibiting mTORC1 with rapamycin shifts cells into a more conservative, stress-resistant, autophagic state — essentially mimicking the cellular response to caloric restriction without actual starvation.

mTORC2 (largely rapamycin-insensitive): Regulates cytoskeletal organisation, cell survival, and glucose metabolism via Akt phosphorylation. Chronic daily rapamycin dosing can eventually inhibit mTORC2 assembly — producing some of the metabolic side effects (insulin resistance, dyslipidaemia) seen in transplant patients on continuous high-dose protocols. This is one key reason why longevity researchers favour intermittent (once-weekly) low-dose rapamycin: it inhibits mTORC1 transiently while allowing mTORC2 to recover between doses.

The autophagy connection: One of the most important consequences of mTORC1 inhibition is activation of autophagy — the cellular process by which damaged proteins, aggregated organelles, and senescent mitochondria are broken down and recycled. Autophagy declines substantially with age in humans, and its reduction is associated with neurodegeneration, immune dysfunction, cardiovascular disease, and cancer. Rapamycin-induced autophagy enhancement is considered one of the primary mechanisms by which it may slow biological aging.

Longevity Evidence — The Key Studies Canadian Users Should Know

NIA Interventions Testing Program (ITP) — mice, 2009 and ongoing: The landmark study. Rapamycin extended median lifespan by 9% in male mice and 14% in female mice — even when treatment began at the mouse equivalent of age 60. This was the first time any drug extended lifespan in a mammal when treatment began in middle age. The study has been replicated multiple times across three independent research sites. Subsequent ITP studies showed even greater lifespan extension when rapamycin was started earlier or combined with other interventions.

Dog Aging Project (DAP) — companion dogs, 2016–ongoing: The first controlled rapamycin longevity study in a companion mammal with shared environment with humans. Middle-aged dogs given low-dose rapamycin (0.05–0.1 mg/kg once weekly) showed measurable improvements in cardiac function (left ventricular wall thickness, ejection fraction) compared to placebo at 10 weeks. The ongoing TRIAD (Test of Rapamycin in Aging Dogs) study is tracking mortality and healthspan outcomes in hundreds of companion dogs. Dogs are considered a uniquely relevant model for human aging research due to shared environment, similar spontaneous diseases, and comparable aging biology.

Banovich et al. (2021) — human cardiac aging: Analysis of cardiac gene expression in aging humans found that rapamycin target genes are among the most significantly dysregulated with age — suggesting the mTOR pathway is centrally involved in human cardiac aging, consistent with the cardiac benefits observed in dogs.

PEARL trial (2019–ongoing) — the first human longevity RCT: Conducted by Ora Biomedical, PEARL is testing intermittent rapamycin dosing in healthy older adults for effects on biomarkers of aging. This is the first randomised controlled trial specifically designed to test rapamycin as a longevity intervention in humans.

Dr. Matt Kaeberlein — University of Washington: One of the world's leading rapamycin longevity researchers and co-founder of the Dog Aging Project. His work has been instrumental in translating rapamycin longevity research from yeast and rodents to dogs and humans, and in establishing the intermittent low-dose protocol widely used in the longevity community.

Dr. Peter Attia, Dr. David Sinclair, and the longevity physician community: A growing number of Canadian and North American longevity-focused physicians now include rapamycin in their personal protocols or prescribe it off-label to healthy adults — making it one of the most discussed pharmaceuticals in the emerging longevity medicine field.

Rapamycin Brand (Rapamune/Wyeth/Pfizer) vs Generic Sirolimus

Rapamune (brand): Manufactured by Wyeth (now Pfizer), Health Canada-approved, available at Canadian pharmacies with prescription. Brand-name drug at significantly higher cost. Available as 0.5 mg, 1 mg, and 2 mg tablets, and as 1 mg/mL oral solution.

Generic Sirolimus (rapamycin generic): Contains identical active pharmaceutical ingredient — sirolimus — at the same dose, manufactured to GMP standards. Bioequivalent to Rapamune. Significantly lower cost. Available at drugs-canada.com from $5.24 per 1 mg pill. For longevity users taking weekly doses of 2–6 mg, the cost difference between brand and generic is substantial over months and years of use.

Important for transplant patients: If you are a renal transplant patient on Rapamune, do not switch to generic sirolimus without consulting your transplant nephrologist — therapeutic drug monitoring (sirolimus trough levels) is required, and even small differences in bioavailability between formulations can affect immune protection and rejection risk. Switching between formulations in transplant patients requires careful monitoring and dose adjustment.

Off-Label Longevity Dosing Protocol — What the Research Community Uses

Important disclaimer: The following describes dosing protocols discussed in the longevity medicine literature and used by some Canadian physicians and researchers. This is entirely off-label — rapamycin is not approved by Health Canada for longevity or anti-aging use. Always consult a physician before starting rapamycin for any indication.

Why intermittent dosing? Continuous daily dosing at transplant doses (2–5 mg/day) produces sustained mTORC2 inhibition leading to insulin resistance, dyslipidaemia, and immunosuppression — side effects that are acceptable in transplant patients because the alternative is organ rejection, but are unacceptable for healthy adults. Intermittent once-weekly dosing produces transient mTORC1 inhibition sufficient to activate autophagy and potentially slow cellular aging, while allowing mTORC2 to recover between doses — dramatically reducing metabolic side effects.

Typical longevity protocol (as discussed in the literature):

• Starting dose: 2 mg once weekly — taken on the same day each week, with food
• Titration: After 4–8 weeks at 2 mg, some protocols increase to 3 mg, then 4 mg, then 5–6 mg weekly depending on tolerance and individual response
• Typical maintenance range: 2–6 mg once weekly — the majority of longevity physicians and researchers appear to use 4–6 mg/week based on available survey data
• With or without food: High-fat meals increase sirolimus absorption by approximately 35% (tablets) — take consistently either with or without food to maintain predictable exposure
• Drug holidays: Many longevity protocols include periodic breaks (e.g., 3 months on, 1 month off) to allow full mTORC2 recovery, though the optimal cycling schedule is not established

Grapefruit juice: Absolutely avoid — grapefruit potently inhibits CYP3A4, the primary enzyme metabolising sirolimus. Even small amounts of grapefruit can increase sirolimus blood levels by 300–400%, creating risk of serious toxicity.

Drug Interactions — Critical Safety Information

Sirolimus is metabolised by CYP3A4 and P-glycoprotein (P-gp). Drugs that inhibit or induce these pathways can dramatically increase or decrease sirolimus blood levels — creating risk of toxicity or loss of efficacy:

Strong CYP3A4 inhibitors — dramatically increase sirolimus levels (avoid or use with extreme caution):

• Ketoconazole, itraconazole, voriconazole, posaconazole (antifungals)
• Ritonavir, cobicistat, other HIV protease inhibitors
• Clarithromycin, telithromycin (antibiotics)
• Grapefruit and grapefruit juice — absolute avoidance required

Strong CYP3A4 inducers — dramatically reduce sirolimus levels (may require dose increase):

• Rifampicin, rifabutin (antituberculosis drugs)
• Carbamazepine, phenytoin, phenobarbital (anticonvulsants)
• St. John's Wort — widely used Canadian herbal supplement, absolutely avoid with sirolimus

Moderate CYP3A4 inhibitors — increase sirolimus levels modestly (use with caution):

• Diltiazem, verapamil (calcium channel blockers — commonly prescribed in Canada for hypertension)
• Fluconazole (antifungal)
• Erythromycin (antibiotic)
• Cyclosporine — used in transplant patients; sirolimus levels increase dramatically when co-administered, requiring dose separation and careful monitoring

Vaccines: Immunosuppressive doses of sirolimus (transplant protocols) reduce vaccine immunogenicity. For longevity doses (once-weekly low dose), the immunosuppressive effect is less pronounced, but discuss timing of vaccinations with your physician — some longevity protocols recommend pausing rapamycin for 2–4 weeks around vaccination to optimise immune response.

Side Effects — Transplant Doses vs Longevity Doses

The side effect profile of rapamycin differs substantially between continuous high-dose transplant protocols and intermittent low-dose longevity use:

At transplant doses (2–5 mg daily, continuous) — commonly reported:

• Mouth ulcers (aphthous stomatitis) — the most frequently reported side effect; often dose-limiting
• Dyslipidaemia — elevated triglycerides and LDL cholesterol (mTORC2 inhibition effect)
• Insulin resistance / impaired glucose tolerance (mTORC2 effect)
• Impaired wound healing — significant surgical consideration; rapamycin is typically held before and after surgery
• Immunosuppression — increased susceptibility to bacterial, viral, and fungal infections
• Oedema, peripheral
• Anaemia, thrombocytopenia
• Interstitial pneumonitis (rare but serious — drug-induced lung inflammation)

At longevity doses (2–6 mg once weekly, intermittent) — reported in the community:

• Mouth ulcers — less common than transplant doses but still the most frequently reported side effect at longevity doses. Some users take supplemental zinc or use prescription mouthwash (Magic Mouthwash) prophylactically
• Mild fatigue in the first 1–2 days after weekly dose — reported by a subset of users
• Mild acne — reported by some longevity users, possibly related to altered skin microbiome
• Metabolic effects (dyslipidaemia, insulin resistance) — substantially less common at intermittent low doses than continuous transplant doses, but monitoring is still recommended
• Immunosuppression at longevity doses — substantially less than transplant doses. The longevity community debate on this continues; many researchers believe intermittent low-dose rapamycin has minimal clinically significant immunosuppression

Rare but serious — seek immediate medical attention:

• Interstitial pneumonitis — drug-induced lung inflammation presenting as progressive dyspnoea, cough, fever. Stop rapamycin immediately and seek care
• Severe hypersensitivity reactions
• Progressive multifocal leukoencephalopathy (PML) — extremely rare, primarily in immunocompromised transplant patients

Who Should Not Take Rapamycin

Rapamycin is contraindicated or requires careful medical evaluation in:

• Patients with known hypersensitivity to sirolimus or any component of the formulation
• Patients with active serious infections (bacterial, viral, fungal) — immunosuppression at any dose may worsen infection
• Patients with significant hepatic impairment — sirolimus is extensively metabolised by the liver; severe hepatic disease substantially increases exposure
• Pregnant or breastfeeding women — sirolimus is teratogenic in animal studies; effective contraception required during treatment and for 12 weeks after stopping
• Patients on strong CYP3A4 inhibitors or inducers — see interaction section above
• Patients scheduled for surgery — rapamycin impairs wound healing and should be held perioperatively (typically stopped 1–2 weeks before elective surgery)

Use with particular caution in: Patients with diabetes or pre-diabetes (risk of worsening insulin resistance at higher doses), patients with dyslipidaemia already on statin therapy, patients with recent or planned vaccinations, patients with chronic infections (HIV, hepatitis B/C), and elderly patients at higher infection risk.

Monitoring Recommendations for Canadian Longevity Users

Canadian physicians prescribing rapamycin off-label for longevity typically recommend the following baseline and ongoing monitoring, drawing from transplant monitoring protocols adapted for lower-dose intermittent use:

• Baseline before starting: Complete blood count (CBC), comprehensive metabolic panel (CMP), fasting lipid panel, fasting glucose and HbA1c, liver function tests, urinalysis
• At 4–8 weeks after starting: Repeat CBC, lipid panel, fasting glucose — to assess early metabolic effects
• Ongoing every 3–6 months: CBC, lipid panel, metabolic panel, HbA1c. Some physicians also monitor sirolimus trough levels (drawn 24 hours after weekly dose) to confirm appropriate exposure
• Immediately if symptoms develop: Progressive breathlessness or cough (interstitial pneumonitis), unusual infections, significant mouth ulcers affecting eating or swallowing

Canadian telehealth platforms including Maple, Dialogue, and Tia Health can provide consultations with physicians familiar with off-label rapamycin use and facilitate lab requisitions for monitoring.

Health Canada Status and Legal Context in Canada

Health Canada approval: Rapamycin (sirolimus) is approved by Health Canada under the brand name Rapamune (Pfizer/Wyeth) for prevention of organ rejection in renal transplant patients. It is a Schedule F prescription drug in Canada — a valid Canadian prescription is required to obtain it at regulated Canadian pharmacies.

Off-label longevity use: Canadian physicians are legally permitted to prescribe any Health Canada-approved drug off-label for indications not listed in the product monograph — including longevity and anti-aging use. A growing number of Canadian longevity-focused physicians and internists are doing so. Finding a Canadian physician willing to prescribe rapamycin for longevity purposes typically requires seeking out physicians with specific interest in longevity medicine or geroscience.

Personal importation grey area: Purchase of generic sirolimus from international online pharmacies for personal use in small quantities exists in a legal grey area under Canadian regulations. Health Canada's Personal Importation Policy allows Canadians to import limited quantities of drugs for personal use under certain conditions. The Agency des services frontaliers du Canada (CBSA) may inspect incoming packages. Enforcement action against individual consumers importing small quantities for personal use is uncommon but not impossible.

Price Comparison — Generic Rapamycin in Canada

Rapamune (brand, Canadian retail pharmacy, with prescription): Approximately CAD$8–15 per 1 mg tablet depending on quantity and province. A standard longevity dose of 5 mg/week costs approximately CAD$40–75 per week at retail brand pricing — CAD$2,000–3,900 per year.

Generic Sirolimus (drugs-canada.com): From $5.24 per 1 mg pill at the smallest quantity, decreasing significantly at larger quantities. A standard longevity dose of 5 mg/week from generic at volume pricing costs a fraction of brand retail.

Delivery to All Canadian Provinces

drugs-canada.com ships discreetly to all Canadian provinces and territories. Standard delivery: 4–9 business days.

Ontario (Toronto, Ottawa, Mississauga, Hamilton, Brampton) — British Columbia (Vancouver, Victoria, Surrey, Kelowna) — Quebec (Montreal, Quebec City, Laval, Gatineau) — Alberta (Calgary, Edmonton, Red Deer) — Manitoba (Winnipeg) — Saskatchewan (Saskatoon, Regina) — Nova Scotia (Halifax) — New Brunswick (Moncton, Fredericton) — and all remaining provinces and territories.

All orders are delivered in plain, unmarked packaging with no reference to the contents or sender. A tracking number is included with every order.

Frequently Asked Questions — Rapamycin in Canada

What is rapamycin used for in Canada? Rapamycin (sirolimus) is Health Canada-approved for prevention of organ rejection in renal transplant patients. Off-label, it is increasingly used by Canadian longevity-focused physicians and patients for its mTORC1-inhibiting properties — based on studies showing lifespan extension in multiple organisms including mice (NIA Interventions Testing Program) and cardiac health improvements in dogs (Dog Aging Project). Off-label longevity use is not approved by Health Canada.

What is the difference between rapamycin and sirolimus? They are the same molecule — sirolimus is the International Nonproprietary Name (INN) for rapamycin. Rapamycin is the common name; sirolimus is the generic drug name used on prescriptions and product labels. Rapamune is the brand name of Pfizer/Wyeth's sirolimus product. Generic sirolimus contains the identical active pharmaceutical ingredient.

What dose of rapamycin is used for longevity? Based on the current longevity medicine literature and physician surveys, the most commonly discussed longevity protocol is 2–6 mg once weekly, typically starting at 2 mg/week and titrating upward based on tolerance. This intermittent dosing approach is chosen to transiently inhibit mTORC1 while allowing mTORC2 recovery between doses — minimising the metabolic side effects seen at continuous transplant doses. This is off-label use. Always consult a physician before starting.

Is rapamycin safe for healthy Canadians? The safety of rapamycin at longevity doses (once-weekly low dose) in healthy adults is an active area of research. At these doses, the side effect profile appears substantially milder than continuous transplant dosing — mouth ulcers are the most commonly reported issue. The PEARL trial and Dog Aging Project are generating prospective human-relevant safety and efficacy data. At transplant doses, rapamycin has a well-established safety profile with known and manageable side effects. Any use by healthy Canadians should be under physician supervision with appropriate monitoring.

Can rapamycin and metformin be taken together? This combination is of significant interest in longevity research — both target overlapping pathways (mTOR and AMPK/mTOR respectively) and may have complementary effects. No serious pharmacokinetic interaction exists between the two. Some longevity physicians use both. However, this is a clinical decision requiring physician input, particularly regarding the combination's effects on glucose metabolism and energy homeostasis.

Does rapamycin suppress the immune system at longevity doses? At continuous transplant doses (2–5 mg daily), rapamycin produces clinically significant immunosuppression. At intermittent longevity doses (2–6 mg once weekly), the immunosuppressive effect is substantially less. Some research actually suggests low-dose intermittent rapamycin may improve certain aspects of immune function in older adults — an area of active investigation. The clinical significance of any immunosuppression at longevity doses is debated in the literature.

How long does delivery to Canada take? Standard delivery to all Canadian provinces takes 4 to 9 business days. All orders arrive in plain, unmarked packaging with no reference to the contents or sender. Every order includes a tracking number.