Which of the following is a possible side effect of Calcium Channel Blockers?

Bradycardia is a known side effect of calcium channel blockers. These medications work by inhibiting calcium from entering the cells of the heart and blood vessels. By doing so, they decrease the force of heart contractions and promote vasodilation, which can lead to a slower heart rate. This is particularly important in conditions such as hypertension or certain arrhythmias, where reducing the heart rate can be beneficial. Therefore, the occurrence of bradycardia aligns with the pharmacological effects of calcium channel blockers, making it a pertinent side effect to recognize.

In contrast to bradycardia, increased heart rate and hypertension are typically not associated with calcium channel blockers, as these medications aim to lower blood pressure and heart rates. Additionally, increased respiratory rate does not directly relate to the primary effects of calcium channel blockers and would not be considered a common side effect of these drugs.