Is fasting required for sirolimus blood concentration testing?

Sirolimus (sirolimus) blood concentration testing requires fasting. Plasma concentration measurement is based on the guidance of pharmacokinetics and uses various sensitive modern analysis methods to determine the drug concentration in the blood. Blood drug concentration is a dynamic change that will change over time as the drug is taken. Diet and drinking water may affect the blood, thereby affecting the blood drug concentration, resulting in inaccurate test results. Therefore, it is generally necessary to maintain a fasting state to measure the blood drug concentration. This is especially true for patients who are likely to experience changes in drug metabolism, patients who are ≥13 years old, weigh less than 40 kg, patients with liver damage, patients whose dosage form of sirolimus has changed, and patients who are taking strong CYP3A4 inducers and inhibitors at the same time.