Drug-drug interactions lead to altered clinical effects, including adverse reactions. Therapeutic drug monitoring of digoxin is necessary due to its narrow therapeutic range. Linezolid can cause variable exposures in patients hospitalized in the intensive care unit owing to its possibility of drug-drug interactions. We present a patient with pneumonia and heart failure who experienced a possible drug interaction between linezolid and digoxin, resulting in high serum concentrations of both drugs. Also, the patient developed thrombocytopenia likely related to linezolid. The linezolid dose required to maintain sufficient levels had to reduce to 50% of the usual linezolid dose. A quarter dose of the standard digoxin dose was needed. Although the underlying mechanism of the drug interaction is unclear, we recommend conducting therapeutic drug monitoring when linezolid and digoxin are administered concurrently.

药物相互作用导致改变的临床效果，包括不良反应。由于地高辛的治疗范围狭窄，因此有必要对治疗药物进行监测。由于利奈唑胺可能与药物相互作用，因此在重症监护病房住院的患者中可能导致不同的暴露水平。我们介绍了一名患有肺炎和心力衰竭的患者，他们经历了利奈唑胺和地高辛之间可能的药物相互作用，导致两种药物的血清浓度较高。另外，患者出现血小板减少症，可能与利奈唑胺有关。维持足够水平所需的利奈唑胺剂量必须减少至通常利奈唑胺剂量的50％。需要标准地高辛剂量的四分之一剂量。尽管药物相互作用的潜在机制尚不清楚，