I know someone who overdosed on verapamil, this person got sick before passing is this something that drug could do. need answer for closure?

Potentially: It depends on what you mean by “sick”. It was not related to the drug if this person developed an infection, cold, or flu. If it was this person’s response to overdose, then possibly. The medication slows down electrical transmissions and slows the heart rate to the point that a person may faint. Other symptoms of overdose include: being mentally out of it, kidney and muscle failure, and coma.