One question I am asked fairly often is regarding the primary metabolite of Heroin; known as 6-AM or 6-MAM. These are synonymous for 6-Acetylmorphine and 6-Monoacetylmorphine (actually all 4 mean exactly the same thing!). For the sake of brevity, in this post I will call it by its most popular moniker: 6-MAM.


Heroin itself has an extremely weak affinity to the μ-opioid receptors, meaning that Heroin itself will essentially not produce any euphoric or pain-relieving effects. However, once it enters the bloodstream, it is immediately metabolized into 6-MAM, which is what actually causes the effects of the drug. Heroin is also metabolized quickly into the less-active 3-Monoacetylmorphine (3-MAM), and less quickly into Morphine. Some forms of Heroin do contain some 6-MAM (most notable would be Black Tar Heroin), but for the most part it is only detectable once the Heroin has been metabolized in the body. As an aside: with regards to drug screening, we are really only concerned with active metabolites, since immunoassays rely on an active chemical reaction to function at all!





*Metabolization of Heroin to 6-MAM


Because 6-MAM is unique to Heroin, many are asking about the availability (as well as the quality and reliability) of an instant test for it so they can make sure they are detecting any Heroin use. While it is available, and the reliability and accuracy are outstanding on the 6-MAM instant test, I typically counsel against testing 6-MAM for a few reasons:

  1. 6-MAM is only detectable in urine for a short time, with barely a 12-hour window of detection.
  2. While 6-MAM has a very short window of detection, the Morphine that is also created as a metabolite takes much longer to purge from one’s system, giving us about a 3-day window of which it can be detected on a standard Opiate panel.
  3. From what we are hearing, so much of the Heroin on the streets these days contains very little (if any) Heroin at all, and it is mostly Fentanyl mixed with other filler. 

So, if you absolutely need to know that the positive Opiate that you are seeing came from Heroin use (as opposed to Morphine or Codeine use), then the 6-MAM panel can provide that information. However, do realize that the window of detection is going to severely limit your ability to detect this substance.