Rapamycin: uses, benefits, and effects on aging

last updated: Feb 22, 2022

3 min read

Rapamycin is a unique drug with many uses. It was originally derived from a compound found on the island of Rapa Nui (known more widely as Easter Island). 

While it’s primarily used for cancer treatment and immune suppression in transplant patients, it also has promising possibilities as an anti-aging drug. 


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What is rapamycin?

Rapamycin, also known as sirolimus or under the brand names Rapamune and Fyarro, is a prescription medication that helps suppress and regulate the immune system. It’s used to treat tumor-based cancers, prevent organ rejection in kidney transplant patients, and coat stents implanted in heart disease patients. 

Studies have also demonstrated that rapamycin may help increase the lifespan and health of elderly people, although more research needs to be done before it’s approved for these uses (Li, 2014).

How does rapamycin work?

Rapamycin blocks cells from growing and multiplying, making it an effective drug to prevent cancer cells from spreading. It also suppresses the immune system of kidney transplant patients to keep the body from rejecting the donor kidney (Hardinger, 2021). 

The drug is able to hinder cell growth by promoting the inhibition of mTOR, which stands for mammalian target of rapamycin. mTOR is a signaling pathway that plays a big role in cell synthesis and metabolism, and rapamycin interrupts it (Selvarani, 2021). 

Since the mTOR pathway is involved in the formation of many health issues (including cancer and Alzheimer’s disease), rapamycin can potentially help treat these conditions. 

What is rapamycin used for?

Rapamycin was originally investigated as an antifungal drug. It’s now used primarily as an anti-tumor and immunosuppressive drug. Here are its FDA-approved uses (Selvarani, 2021): 

  • Cancer treatment: Because rapamycin is able to stop cells from growing and multiplying, it is used to treat particular types of tumors in cancer patients. The brand name Fyarro is the rapamycin drug designed for this purpose.

  • Kidney transplant: Rapamycin is often given in combination with multiple other drugs to help suppress a person’s immune system after they’ve received a kidney organ transplant. This helps prevent the person’s own immune system from perceiving the transplanted kidney as a threat and rejecting it (Hardinger, 2021).

  • Cardiac patients: This medication is also used to coat stents, which are used to prop open blocked arteries in cardiac patients. 

Rapamycin for anti-aging

There’s also some evidence that rapamycin may promote a longer and healthier lifespan. But how could rapamycin do something as far-fetched as lengthening life? 

It comes back to that mTOR pathway (the one rapamycin blocks). Blocking this pathway prompts a process called autophagy, where the body is able to clean up broken and damaged cell parts at a faster rate. 

This means rapamycin has the potential to extend life by preventing aging, cell death, and dysfunction of organ systems (Li, 2014). So far one of the few tools we know reliably increases longevity is fasting, which does so by also blocking the mTOR pathway (Escobar, 2019). 

As exciting as this all may be, most studies on this have been done on mouse models. We’ll need more clinical trials in humans before rapamycin can be recommended for anti-aging (Kaeberlein, 2019; Quarles, 2020). 

There are things you can do on your own as well to promote longevity like eating a diverse diet rich in nutrients and getting regular exercise.

Rapamycin side effects 

There are several possible side effects of rapamycin. Most are mild, but some can be significant or even life-threatening.

Some adverse reactions include (FDA, 2021; PDR, 2022):

  • Sore or inflamed mouth

  • Weakened immune system

  • Anemia and fatigue

  • Constipation or diarrhea

  • Elevated cholesterol or lipid levels

  • High blood pressure

  • Swollen hands and feet

Less frequently, people experience more serious side effects, such as (PDR, 2022): 

  • Blood clots 

  • Stroke or pulmonary embolism

  • Blood clotting problems

Rapamycin dosage 

For kidney transplant patients, rapamycin is taken orally as a tablet or liquid solution for people who can’t swallow pills. It can be taken with food or a large glass of water or orange juice. Keep in mind rapamycin is not safe to take with grapefruit juice. However you take rapamycin, be sure to take it at the same time and in the same way each day (Hardinger, 2021).

For cancer patients, rapamycin treatment is given through an IV. It takes around 30 minutes to be administered (FDA, 2021).

Your healthcare provider will adjust your rapamycin dose based on how your body tolerates it, how it affects your medical condition, and whether you’re experiencing side effects. They may decide to increase the dose, decrease it, or switch you to a different medication altogether.

Rapamycin warnings

There are some people who should not take rapamycin. It isn’t safe for pregnant or breastfeeding women or people who have a sensitivity to rapamycin. 

Rapamycin should also only be used to prevent organ rejection in kidney transplant patients, but never in liver or lung transplant patients, due to an increased risk for serious complications (FDA, 2017).

Rapamycin interactions

There are several medications you should not take at the same time as rapamycin. These include live vaccines since rapamycin suppresses your natural immunity

Other drugs––like antivirals used to treat hepatitis C and mifepristone for Cushing’s syndrome––should be avoided as the combined effect could dangerously boost rapamycin levels (PDR, 2022).


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

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Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

February 22, 2022

Written by

Nancy LaChance, BSN, RN

Fact checked by

Steve Silvestro, MD

About the medical reviewer

Dr. Steve Silvestro is a board-certified pediatrician and Associate Director, Clinical Content & Education at Ro.