The Opiate Drugs, Codeine, Morphine, and Heroin, Are Highly Effective

The opiate drugs, codeine, morphine, and heroin, are highly effective painkillers, but they are dangerous. Why?

A) While the manufacture of the drugs themselves is legal, the original source of them, opium, is not, so they support crime networks.
B) They are also stimulants and can raise your heart rate and blood pressure to the point where you're at high risk of a stroke.
C) They interact dangerously with commonly used drugs like nicotine.
D) They are highly addictive and so once started, it's difficult to stop using them
E) The manufacture of these drugs tends to be "underground," so there is a high risk of contamination.