Lyric discussion by MrCarder 

Cover art for Don't Break The Needle lyrics by J Roddy Walston & The Business

I couldn't find anything to support this, but I get the impression that this song is about Heroine.

He mentions a "sick forcep" in the first line. The forcep being a common area to insert the needle. I'm assuming the tricep reference in the second line is also about a part of the process of "shooting up" - which is mentioned soon after.

I also think "pulling thread" is an awesome name for shooting heroine.

My Interpretation