Tacrolimus Capsules (Astagraf XL) are calcineurin inhibitor-type immunosuppressants used in kidney transplant patients to prevent organ rejection. To optimize therapeutic efficacy and reduce the risk of adverse reactions, the drug must be administered in strict accordance with the principle of individualized dosing during use, and dosage adjustments should be made based on the patient’s specific conditions.
How to Use Tacrolimus Capsules (Astagraf XL)
Correct Administration Method
Tacrolimus Capsules must be swallowed whole; they should not be chewed, split, or crushed.
It is recommended that patients take the medication on an empty stomach at a fixed time every morning—either 1 hour before a meal or 2 hours after a meal.
To avoid drug interactions, patients should refrain from consuming grapefruit, drinking grapefruit juice, or consuming alcoholic beverages during the treatment period.
If a dose is missed, the missed dose should be taken within 14 hours (e.g., if the scheduled dose is at 8:00, the latest time to make up the dose is 22:00). If more than 14 hours have passed, skip the missed dose and take the regular dose the next morning. Double doses are strictly prohibited.
Special Handling Recommendations
When a dose is missed, the "14-hour rule" must be followed for remedial dosing.
Special attention should be paid to the fact that different tacrolimus dosage forms are not interchangeable; any change in dosage form must be carried out under the supervision of a physician.
Dosage Adjustment of Tacrolimus Capsules (Astagraf XL)
Monitoring of Blood Drug Concentration
During treatment, regular monitoring of whole-blood trough concentrations is required:
For adult patients: The target concentration is 7–15 ng/mL within 1 month after surgery, 5–15 ng/mL from 2 to 6 months after surgery, and maintained at 5–10 ng/mL after 6 months.
It is recommended to perform concentration testing at least twice on different days in the early stage of treatment, after dosage adjustment, or when combining with CYP3A4 inducers/inhibitors or cannabidiol.
Dosage Adjustment Based on Influencing Factors
African American patients usually require higher doses to achieve blood drug concentrations comparable to those in white patients.
Patients with severe hepatic impairment need to have their initial dose reduced.
Strong CYP3A inducers may lower tacrolimus blood concentrations, increasing the risk of rejection; strong CYP3A inhibitors may increase tacrolimus blood concentrations, raising the risk of adverse reactions.
Medication for Special Populations of Tacrolimus Capsules (Astagraf XL)
Patients with Hepatic or Renal Impairment
Patients with severe hepatic impairment need to have their initial dose reduced.
Patients with renal impairment also require renal function monitoring, and dosage reduction should be implemented based on clinical indicators.
Pregnant and Lactating Women
Tacrolimus may cause harm to the fetus; the risks and benefits must be carefully weighed when administering the drug to pregnant women.
Lactating women should exercise caution, as the drug is excreted in breast milk.
Pediatric Patients
Pediatric patients aged 4 years and older who can swallow capsules whole may use this drug. Studies on pediatric patients aged 4–15 years have shown that their pharmacokinetic parameters are comparable to those of adults.
Geriatric Patients
It is recommended to start administration at the lower end of the dosage range. Comprehensive consideration should be given to the often accompanying decline in hepatic and renal function and concurrent medications in geriatric patients.
