Final answer:
The most commonly reported side effect of Verapamil (Calan) is constipation. This medication may cause various side effects, but gastrointestinal issues such as constipation are most frequent, while fatigue and muscle aches are reported as well.
Step-by-step explanation:
The most commonly reported side effect of Verapamil (Calan) is constipation. While this medication can have multiple side effects due to its mechanism of action as a calcium channel blocker, including possibilities like indigestion, nausea, and muscle aches, it is widely recognized that gastrointestinal issues, specifically constipation, are the most frequent.
It's also important to note that individual responses to medication can vary, and other common side effects, such as fatigue and muscle aches, could occur. However, constipation remains the most commonly reported adverse effect among patients taking Verapamil. Support and information regarding mental health conditions and the side effects of medications like antidepressants suggest that constipation is also a shared side effect in these drugs.