Metals, toxins and medication
Heroïne (6-acetylmorfine)
A urine test for 6-acetylmorphine, which only forms after heroin use; says something about use in the past day.
Everything about this testWhat it measures
In the body, heroin is quickly converted into 6-acetylmorphine (6-MAM) and then into morphine. 6-acetylmorphine is only formed from heroin and not from poppy seeds, codeine or morphine as a medicine. This means the test can distinguish heroin use from other causes of a positive opiate test. The breakdown product does disappear quickly and is only detectable in the urine for a short time.
- Recent use of heroin, usually within the past day
Positive
A positive result means there is 6-acetylmorphine in the urine above the laboratory's limit. This fits heroin use shortly before the urine was collected, usually within the past day. Heroin that a doctor prescribes in the treatment of heroin addiction also gives a positive result. A positive result shows that a substance is in the body; it is not a diagnosis and says nothing about dependence, the amount or the time of use.
Negative
A negative result means no 6-acetylmorphine was found above the laboratory's limit. Because the substance disappears quickly, this does not rule out heroin use more than about a day ago. Morphine, the next breakdown product, stays detectable longer: according to the Trimbos Institute, 2 to 4 days after heroin use. Diluted urine from drinking a lot can bring the value below the limit.
If your result is abnormal
With a positive result that may have consequences, the laboratory has the result confirmed with a second method of analysis. The GP then looks at the context: frequency, symptoms and any wish to quit, and refers to addiction care if needed.
Reliability
A positive result for 6-acetylmorphine points more specifically to heroin than a standard opiate test, but the window is short, so a negative result says little. The Dutch Society for Clinical Chemistry (NVKC) states that a positive result of a screening test must be confirmed with a second, different method of analysis; a confirmation test is not included in this test.
Limitations
- 6-acetylmorphine is only detectable for a short time; use more than about a day ago is usually missed.
- A screening test can give a false-positive result; confirmation with a different method is needed before a result can carry weight.
- Heroin that a doctor prescribes in the treatment of addiction also gives a positive result.
- Fluid intake determines how concentrated the urine is; diluted urine can give a negative result.
How common is this
Heroin use is uncommon in the Netherlands: in 2025, 0.5 percent of adults had ever used heroin. It mainly concerns a small, often older group of long-term users.
Who is this useful for
Useful for a medical question, for example in addiction care, or when an opiate test is positive and the question is whether this comes from heroin or from poppy seeds or a medicine. Because the substance is only detectable for a short time, the test mainly says something if the urine is collected shortly after possible use.
Downsides and risks
- A negative result can give false reassurance, because 6-acetylmorphine is only detectable for a short time.
- A result without a confirmation test can wrongly be used as evidence.
Sources
Always discuss an abnormal result with your GP. If a result is strongly abnormal, we try to reach you as soon as possible. Read your result yourself as well and contact your GP if in doubt. A test does not make a diagnosis. Read more about risks and results