I understand that accidentally shooting heroin into an artery can cause horrible things to happen, including gangrene that necessitates amputation. But I don't understand HOW--what is the mechanism of action that causes complications?
I saw a friend hit an artery earlier tonight--he said he could feel the junk flowing toward his hand, and how it felt like every cell in his hand was screaming in pain. Many people post that it takes hours for their swelling to go down, but he didn't experience any measurable swelling, and the pain subsided in less than three or four minutes.
Based on the fact that there is no swelling and that the pain died so quickly, he doesn't expect to go to the ER unless things get worse, but he would like to have a more detailed understanding of exactly what might happen in his arm after his artery hit, so that he can make an informed decision about whether to run to the ER or not. Can anybody help, or point me toward somewhere else that will?