Which medication can be used to increase heart rate in a patient with symptomatic sinus bradycardia?

Atropine is an anticholinergic medication that works by blocking the effects of the vagus nerve on the heart, thereby increasing heart rate. In cases of symptomatic sinus bradycardia, where the heart rate is abnormally slow and the patient is experiencing symptoms such as dizziness or fatigue, atropine is often the first-line treatment. It increases the conduction through the atrioventricular (AV) node and helps restore a more normal heart rhythm.

This mechanism makes atropine particularly effective in treating bradyarrhythmias caused by excessive vagal tone or certain types of AV block. The administration of atropine leads to increased heart rate and improved blood flow to the organs, relieving the symptoms associated with bradycardia.

In contrast, medications like atenolol and amiodarone are typically used to manage other types of arrhythmias or conditions where a decreased heart rate is not beneficial. Dopamine can also increase heart rate but is not the first choice for treating sinus bradycardia specifically; it is more commonly used in cases of shock or heart failure where blood pressure support is necessary.