Will taking crizotinib cause a decrease in heart rate?

Taking crizotinib may cause a decrease in heart rate. Crizotinib is a tyrosine kinase inhibitor mainly used to treat ALK-positive or ROS1-positive non-small cell lung cancer. Based on published studies and drug labels, crizotinib may cause a decrease in heart rate during treatment. Specifically, for every 100 ng/mL increase in serum crizotinib concentration, the heart rate slowed down on average 2.5 times / minutes (bpm). In addition, studies have shown that the incidence of grade 1-2 sinus bradycardia (heart rate less than 60 bpm) in patients taking crizotinib was 5%.

The specific mechanism by which crizotinib causes a decrease in heart rate is not fully understood, but may be related to the drug's effect on cardiac electrophysiological activity. Crizotinib may affect the function of cardiac ion channels, thereby changing cardiac conductivity and rhythm, leading to a decrease in heart rate.

In most patients, the decrease in heart rate caused by crizotinib is usually mild and not associated with severe symptoms. However, for some patients, particularly those with pre-existing heart disease or who are taking other medications that may affect heart rate, a decrease in heart rate may increase the risk of a cardiac event. Therefore, during the use of crizotinib, doctors need to pay close attention to the patient's heart rate changes and perform corresponding monitoring and treatment as needed.

While taking crizotinib, patients should regularly monitor heart rate and blood pressure so that any abnormalities can be detected and dealt with promptly. If patients need to take other drugs that may affect heart rate at the same time, they should consult their doctor in advance to avoid drug interactions that may cause a further decrease in heart rate. If a patient develops a severe heart rate drop or other symptoms of cardiac discomfort while taking crizotinib, he or she should seek medical attention immediately and inform the doctor of the ongoing use of crizotinib.