Home Drug Guide Sirolimus

Drug Guide

Generic Name

Sirolimus

Brand Names Rapamune, Fyarro, Hyftor

Classification

Therapeutic: Immunosuppressant, Antineoplastic

Pharmacological: mTOR inhibitor

FDA Approved Indications

  • Prophylaxis of organ rejection in kidney transplant patients
  • Treatment of certain cancers (e.g., relapsed or refractory Hodgkin lymphoma, systemic anaplastic large cell lymphoma)

Mechanism of Action

Sirolimus inhibits the mammalian target of rapamycin (mTOR), a kinase involved in cell proliferation, growth, and survival, thereby suppressing T-cell and B-cell proliferation that are dependent on IL-2.

Dosage and Administration

Adult: Dose varies based on indication; for kidney transplant, initial dose is typically 6 mg once daily, adjusted to target blood levels.

Pediatric: Use with caution; dosing is based on weight and clinical response.

Geriatric: Start at lower doses due to potential increased sensitivity.

Renal Impairment: Adjust dosage based on blood levels and renal function.

Hepatic Impairment: Adjustments may be necessary; monitor liver function closely.

Pharmacokinetics

Absorption: Excellent oral bioavailability (~14%).

Distribution: Extensively bound to erythrocytes and plasma proteins.

Metabolism: Primarily hepatic via CYP3A4 and P-glycoprotein.

Excretion: Metabolites excreted mainly via feces; minimal urinary excretion.

Half Life: Approximately 62 hours in adults, allowing once-daily dosing.

Contraindications

  • Known hypersensitivity to sirolimus or sirolimus-containing products.

Precautions

  • Monitor lipid levels; risk of hyperlipidemia.
  • Assess for signs of infection; immunosuppression increases infection risk.
  • Use with caution in patients with hepatic impairment.

Adverse Reactions - Common

  • Infections (e.g., respiratory, urinary, skin infections) (Very common)
  • Hyperlipidemia (hypertriglyceridemia, hypercholesterolemia) (Common)
  • Myelosuppression (thrombocytopenia, leucopenia, anemia) (Common)
  • Stomatitis/mucositis (Common)

Adverse Reactions - Serious

  • Pneumonitis (interstitial lung disease) (Less common)
  • Hepatotoxicity (Less common)
  • Delayed wound healing (Less common)
  • Lymphocele or seroma formation (Less common)

Drug-Drug Interactions

  • CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin) increase sirolimus levels.
  • CYP3A4 inducers (e.g., rifampin, carbamazepine) decrease levels.

Drug-Food Interactions

  • Grapefruit and grapefruit juice may increase sirolimus levels.

Drug-Herb Interactions

  • St. John’s Wort may reduce effectiveness.

Nursing Implications

Assessment: Monitor for signs of infection, wound healing, lipid profile, renal and liver function, blood counts, and sirolimus blood levels.

Diagnoses:

  • Risk for infection
  • Impaired tissue integrity
  • Imbalanced nutrition: less than body requirements (due to gastrointestinal symptoms)

Implementation: Administer as prescribed, monitor drug levels regularly, observe for adverse reactions, educate patient about infection control.

Evaluation: Assess effectiveness in preventing rejection or controlling cancer, monitor side effects, adjust dosage accordingly.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Report signs of infection (fever, sore throat, cough).
  • Avoid grapefruit juice.
  • Keep appointments for blood tests.
  • Notify provider for wound issues or unusual symptoms.

Special Considerations

Black Box Warnings:

  • Risk of increased susceptibility to infection and lymphoma due to immunosuppression.
  • Potential for hypersensitivity reactions.

Genetic Factors: Pharmacogenetic testing is not routinely performed but may influence metabolism.

Lab Test Interference: May affect lipid levels, liver enzymes, renal function, and blood counts.

Overdose Management

Signs/Symptoms: Severe immunosuppression, bleeding, toxicity signs.

Treatment: Supportive care; no specific antidote. Hemodialysis not effective due to extensive tissue binding.

Storage and Handling

Storage: Store at room temperature (20-25°C), away from moisture and light.

Stability: Stable through expiration date if stored properly.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.