If it was injected its already in the body but what your calling missed I'm sure is just as bath as using the drug in the first place if not worse. Definitely go to the hospital don't self diagnose this online. Yeah someone could have been through the same thing but what it does to the body could have a dramatically different effect from person to person so please get professional help. I'm not judging your friend but maybe they could help get him off the drug altogether. Best wishes and prayers!