It is unfortunate that the song 'Heroin', by the Velvet Underground, is called just that. I've heard it said that it was written by Lou Reed at the age of 19, and it is certainly strange that a song that can touch so well on so many general and specific points of the human condition should be written by one so young, and so illiterate.
The song could have been written, and been as famous as it was, without mention of heroin. It has given it a great deal of fame, or infamy, but the discussion of nilhism would have been just as meaningful if it was called "Heading for the Kingdom", or something of the sort. In many ways, I must compare this song to the songs of The Pixies. Many Pixies songs contain just this strong of images, of messages, without ever giving the listener an obvious hook to distract them from that message, to fix it falsely in their head.
Heroin to me, is a song about a royal system. The line about "heading for the kingdom" is not coincidence, neither is the line about "being Jesus' son", and the blood is not the blood that carries the heroin to his brain, but the blood that carries the sacred lineage of the ancestor king. The system of royalty, which turns people into subjects instead of citizens, makes people the passive subjects of whatever happens to them, makes them consent to whatever happens, emerging them in an ouroboric reality, where nothing matters but the continued cycle of royal whims, or of heroin addiction. It takes away the responsibility to think, and to care. Perhaps heroin can make people forget the bodies piled up in mounds, but for most people, the narrative of national conquest works much better.
The line about "Jesus' son" may seem a bit odd, and is in fact jarring, but it should be remembered that in some countries today, being a descendant of a mythic god-ancestor is the only way to be a member of that society. And being on a personal mission to accomplish God's kingdom on Earth has caused more abdication of moral thinking than a crippiling physical addiction ever could.
I do not at all mean that this should be seen as a literal interpretation of what a dumb teenager dreamed up in his mind one day, but in not being literal, or directly connected, it becomes all the more true.