Can a cardiac arrest be caused by any drug toxicity?

Absolutely: Many drugs , if taken in excess, that regulate heart rate can cause a cardiac arrest. In particular drugs like digoxin is a major contributor to emergency room toxicity visits among the elderly.

Yes: Many drugs that regulate heart rate can cause cardiac arrest if taken in excess. These may include digitalis, beta blockers, calcium channel blockers, etc.

Absolutely: Not even including recreation drugs, an overdose of any of which may cause cardiac arrest, prescription drugs such as many heart or blood pressure medicines, water pills, potassium supplements and many, many others can do this, the list is a mile long!