FCEM-0264

A 39-year-old man with a long history of depression presents after intentionally overdoing his heart medication. Verapamil immediate-release 240 mg is the tablet he takes for this condition, he says. He took the pills about 30 minutes ago, but his wife discovered him right away and rushed him to the emergency room.

At the moment, he is completely symptom-free. When it comes to this type of overdose, how long does it usually take for symptoms to appear?