Sirolimus
Pronunciation: (ra-PAM-i-sin).
- Generic name
- Sirolimus
- Brand names
- Sirolimus, Rapamune, Siromus, Siroboon, Rapacan
- Drug class
- Immunosuppressant (mTOR inhibitor)
Availability and supply rules vary by country
Trade names by country: United States · Canada
Australia: · Full directory
What Sirolimus is and how it works
Uses, formulations, monitoring, and supply rules can differ by patient, product, and country. Follow the exact local product information and professional advice.
Mechanism of action: how Sirolimus works
Rapamycin (sirolimus) is a macrolide compound that inhibits the mammalian target of rapamycin (mTOR), a serine/threonine kinase involved in cell cycle progression, proliferation, and survival. By binding to the immunophilin FKBP-12, rapamycin forms a complex that inhibits mTORC1, leading to suppression of T-lymphocyte activation and proliferation, thereby reducing immune-mediated rejection of transplanted organs. (2)
What Sirolimus is used for
Kidney transplant rejection prophylaxis
Kidney transplant rejection prophylaxis (2)
Lymphangioleiomyomatosis (LAM)
Lymphangioleiomyomatosis (LAM) (2)
Tuberous sclerosis complex (TSC)-associated angiomyolipoma
Tuberous sclerosis complex (TSC)-associated angiomyolipoma (2)
Tuberous sclerosis complex (TSC)-associated subependymal giant cell astrocytoma (SEGA)
Tuberous sclerosis complex (TSC)-associated subependymal giant cell astrocytoma (SEGA) (2)
Before taking Sirolimus
Do not take / not appropriate for
- hypersensitivity to sirolimus or its components. (Contraindication) (2)
- Avoid use in pregnancy and lactation. (Contraindication) (2)
Tell your clinician about
(2)How to take Sirolimus
- General Instructions: Take rapamycin exactly as prescribed, at the same time each day, with or without food, but always in the same way (either always with food or always without food).. Adult Dosing: Typical starting dose for kidney transplant: 6 mg orally once, then 2 mg once daily. Dose may be adjusted based on blood levels and response.. Pediatric Dosing: Dosing in children is individualized based on weight and clinical response. Close monitoring is required.. Administration: Swallow tablets whole; do not crush or chew. Oral solution should be measured carefully with the provided syringe. If switching between oral solution and tablets, your doctor will adjust the dose.. When To Stop: Do not stop taking rapamycin without your doctor's advice, even if you feel well. Stopping suddenly can increase the risk of organ rejection.. Storage: Store at room temperature away from moisture and heat. Keep oral solution refrigerated and use within the recommended period after opening.
- This page does not provide a dose calculator. Dosing must follow the prescriber, pharmacist, or product label.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (2)
Missed dose
If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose—do not double up. Contact your healthcare provider if you miss more than one dose.
Overdose
In case of overdose, seek emergency medical help or contact a poison control center immediately. Symptoms may include severe immunosuppression, increased risk of infection, or organ dysfunction. Supportive care and monitoring are essential. (2)
Side effects
Side effects and their urgency vary; report severe, persistent, or concerning symptoms to a healthcare professional.
Mouth sores
Incidence: Reported in the clinician-authored database; frequency not established
Diarrhea
Incidence: Reported in the clinician-authored database; frequency not established
High blood sugar
Incidence: Reported in the clinician-authored database; frequency not established
High cholesterol
Incidence: Reported in the clinician-authored database; frequency not established
Swelling (edema)
Incidence: Reported in the clinician-authored database; frequency not established
Anemia
Incidence: Reported in the clinician-authored database; frequency not established
Increased risk of infection
Incidence: Reported in the clinician-authored database; frequency not established
Kidney problems
Incidence: Reported in the clinician-authored database; frequency not established
Serious warnings
US FDA BOXED WARNING — Increased susceptibility to infection and possible development of lymphoma and other malignancies (especially skin cancer) may result from immunosuppression — serious
Symptoms: US FDA BOXED WARNING — Increased susceptibility to infection and possible development of lymphoma and other malignancies (especially skin cancer) may result from immunosuppression; only physicians experienced in immunosuppressive therapy and management of transplant patients should prescribe sirolimus. Use in liver transplant patients is not recommended (associated with increased risk of hepatic artery thrombosis, some leading to graft loss or death). Use in lung transplant patients is not recommended (associated with bronchial anastomotic dehiscence, some fatal).
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Contraindications recorded in the clinician database — serious
Symptoms: Contraindications recorded in the clinician database: Contraindications include hypersensitivity to sirolimus or its components. Use with caution in patients with hepatic impairment, hyperlipidemia, or history of infections. Avoid use in pregnancy and lactation. Monitor for delayed wound healing and increased risk of malignancy.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
May increase cholesterol and triglyceride levels, requiring monitoring and possible lipid-lowering treatment — serious
Symptoms: May increase cholesterol and triglyceride levels, requiring monitoring and possible lipid-lowering treatment. Can delay wound healing and increase the risk of fluid accumulation (peripheral edema, lymphedema, pleural/pericardial effusion). Not recommended during pregnancy or breastfeeding.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Recorded interactions | Rapamycin interacts with many medications, including strong CYP3A4 inhibitors (such as ketoconazole, clarithromycin), anticonvulsants (such as phenytoin, carbamazepine), and certain antibiotics. These interactions can increase or decrease rapamycin levels, affecting its efficacy and safety. Always inform your healthcare provider about all medicines and supplements you are taking. | (1) |
Pregnancy, breastfeeding, kidney/liver function, age
Pregnancy
Sirolimus can cause fetal harm based on animal data; the FDA label reviewed for this page advises females of reproductive potential to use effective contraception before starting sirolimus, during treatment, and for 12 weeks after the final dose. Discuss any pregnancy or plan for pregnancy with the transplant team before starting or continuing treatment. (2)
Breastfeeding
The FDA label reviewed for this page states sirolimus is present in the milk of lactating rats; because of the potential for serious adverse reactions in a nursing infant, women should not breastfeed while taking sirolimus. (2)
Children
Frequency: Not recommended for pediatric use.. Weight Based: Not established for pediatric use.. Max Daily Dose: Not recommended for pediatric use.. Max Single Dose: Not recommended for pediatric use.. Age Restrictions: Safety not established in children. (2)
Renal_impairment
Per the FDA label reviewed for this page: hepatic impairment — reduce the maintenance dose by approximately one-third in mild-to-moderate hepatic impairment and by approximately one-half in severe hepatic impairment (the loading dose does not need to be changed); therapeutic drug monitoring is required in all patients with hepatic impairment. Renal impairment — no dosage adjustment is required, because minimal (about 2.2%) of the drug or its metabolites is excreted renally. (2)
Hepatic_impairment
Per the FDA label reviewed for this page: hepatic impairment — reduce the maintenance dose by approximately one-third in mild-to-moderate hepatic impairment and by approximately one-half in severe hepatic impairment (the loading dose does not need to be changed); therapeutic drug monitoring is required in all patients with hepatic impairment. Renal impairment — no dosage adjustment is required, because minimal (about 2.2%) of the drug or its metabolites is excreted renally. (2)
Monitoring
(2)Storage
Per the FDA label, store sirolimus tablets at 20-25 degrees C (68-77 degrees F), protected from light; store the oral solution in the refrigerator (2-8 degrees C), protected from light, and use within the manufacturer-stated period after opening (the label states the oral solution may be kept at room temperature for a short period if refrigeration is not possible, but should still be used promptly and protected from light).
Professional information
Clinician-facing context only. This section does not replace current product labeling.
General
Indication: Kidney transplant rejection prophylaxis
Dose summary: Initial loading dose of 6 mg orally once, followed by a 2 mg once-daily maintenance dose (lower loading/maintenance doses are used in low-to-moderate immunologic risk renal transplant patients per the label); doses are then individualized using therapeutic drug monitoring (target trough levels).
Renal context: Per the FDA label, no dosage adjustment is required for renal impairment, because only a minimal fraction (about 2.2%) of sirolimus or its metabolites is excreted in the urine. (1) (2)
Frequently asked questions
What is rapamycin used for?
Rapamycin is mainly used to prevent organ rejection in kidney transplant patients. It may also be used off-label for certain rare diseases and research purposes.
How does rapamycin work?
Rapamycin blocks the mTOR protein, which helps control cell growth and immune responses. This reduces the activity of immune cells that could attack a transplanted organ.
Can I take rapamycin if I am pregnant or breastfeeding?
Rapamycin is not recommended during pregnancy or breastfeeding due to potential risks to the baby. Discuss family planning with your doctor before starting this medication.
What should I do if I miss a dose?
Take the missed dose as soon as you remember, unless it is almost time for your next dose. Do not double up. Contact your doctor if you miss more than one dose.
Are there foods or drinks I should avoid?
Yes, avoid grapefruit and grapefruit juice, as they can increase rapamycin levels and risk of side effects.
What are the most serious side effects?
Serious side effects include severe infections, allergic reactions, delayed wound healing, and increased risk of certain cancers. Seek medical attention if you experience any severe symptoms.
How is rapamycin monitored?
Regular blood tests are needed to check rapamycin levels, kidney function, cholesterol, and blood counts. Your doctor will adjust your dose based on these results.
What happens if I take too much Rapamycin?
Taking too much Rapamycin can lead to severe side effects, including increased risk of infection, kidney problems, and bone marrow suppression. Symptoms may include unusual bleeding or bruising, fever, or extreme fatigue. If you suspect an overdose, seek emergency medical attention immediately or contact your local poison control center. Do not attempt to self-treat.
Can I drink alcohol while taking Rapamycin?
It is generally advisable to avoid or limit alcohol consumption while taking Rapamycin. Alcohol can exacerbate some of the drug's side effects, such as liver toxicity, and may also interfere with the drug's metabolism, potentially altering its effectiveness and increasing adverse reactions. Always consult your healthcare provider for personalized advice regarding alcohol intake with your medication.
Is Rapamycin safe during pregnancy?
Rapamycin is generally not recommended during pregnancy due to potential risks to the fetus. It falls into a category where the risks may outweigh the benefits, especially given its immunosuppressive properties. If you are pregnant, planning to become pregnant, or breastfeeding, it is crucial to discuss the risks and benefits with your healthcare provider to determine the safest course of action.
What is the mechanism of action of Sirolimus?
Rapamycin (sirolimus) is a macrolide compound that inhibits the mammalian target of rapamycin (mTOR), a serine/threonine kinase involved in cell cycle progression, proliferation, and survival. By binding to the immunophilin FKBP-12, rapamycin forms a complex that inhibits mTORC1, leading to suppression of T-lymphocyte activation and proliferation, thereby reducing immune-mediated rejection of transplanted organs. (2)
What is the generic name of Sirolimus?
The generic name is Sirolimus. It is sold under brand names including Sirolimus, Rapamune, Siromus, Siroboon, Rapacan.
What class of drug is Sirolimus?
Sirolimus is classed as: Immunosuppressant (mTOR inhibitor).
References
- UnresolvedUnresolved · Unresolved · dated Unresolved · accessed 2026-08-07 · source 1
- UnresolvedUnresolved · Unresolved · dated Unresolved · accessed 2026-08-07 · source 2
- SIROLIMUS TABLET [REMEDYREPACK INC.] — US prescribing information (DailyMed SPL)U.S. National Library of Medicine (DailyMed) · US · accessed 2026-08-14 · source 3
- Sirolimus — patient drug information (MedlinePlus)U.S. National Library of Medicine (MedlinePlus) · US · accessed 2026-08-14 · source 4
- sirolimus — FDA approval record (Drugs@FDA ANDA201676)U.S. Food and Drug Administration · US · accessed 2026-08-14 · source 5
- Sirolimus — RxNorm normalized drug concept (RXCUI 35302)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 6
Brand names by country
Single-ingredient Sirolimus names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- HYFTOR2 mg/g · nobelpharma america, llc
- FYARRO5 mg/mL · aadi bioscience, inc.
Canada
- RAPAMUNE