A relapse during abstinence, whether a positive value or a missed test appointment, usually invalidates the ongoing programme: the abstinence clock starts again. That is annoying and costs time, but it does not mean the end of your MPU (medical-psychological assessment, Medizinisch-Psychologische Untersuchung). What matters now is not to cover anything up, to understand the cause and to restart properly.
What does a positive value in the abstinence programme mean?
A positive value in the abstinence programme means that proof of continuous abstinence (Abstinenznachweis) can no longer be provided for the period so far. As a rule, the ongoing programme is therefore invalidated. For your MPU, only the new testing period without gaps from the restart then counts.
Depending on the method, alcohol can be detected for different lengths of time: EtG can be detected in urine for about 24–80 hours, and in hair retrospectively for about 3 months (max. 3 cm per analysis). The blood value PEth reflects consumption over roughly the last 2–4 weeks; a value below 20 ng/ml is regarded as the limit for abstinence. That is why even a single "slip" can become visible.
Does a missed appointment also count as a relapse?
A missed appointment does not count as consumption, but it can invalidate the programme in the same way. Abstinence programmes following CTU criteria depend on appointments being unannounced and on you usually reporting to give a sample within about 24 hours. If an appointment is missed, a gap arises, and the programme must run continuously to be recognised.
Whether a missed appointment can still be explained in the individual case is something you should clarify immediately with your laboratory or programme provider. In principle, however, plan on the basis that a gap can mean a restart.
| Event | Possible consequence | What you should do |
|---|---|---|
| Positive EtG or PEth value | Programme usually invalidated, clock starts again | Assess it honestly, work through the cause, restart |
| Missed test appointment | A gap can invalidate the programme | Contact the laboratory immediately and clarify |
| Dyed/bleached hair before hair EtG | Analysis unusable | Switch to urine or PEth |
| Food containing alcohol/mouthwash | EtG can test positive | Avoid if in doubt |
Why should you not cover up a relapse?
You should not cover up a relapse, because a concealed relapse that comes to light later costs you all your credibility. Assessors check the consistency between the case file, the questionnaire, lab values and your account. Contradictions are noticed immediately.
Also stay well away from supposed shortcuts: "ready-made" proof, clean values for money or backdated programmes are forgery of documents (Urkundenfälschung). With them, you put far more at risk than just your MPU.
Honesty, on the other hand, is part of what assessors want to see. In the interview, you are explicitly asked what your plan is in case of a relapse or a "slip". If you can openly assess a real relapse and draw consequences from it, you show insight into the problem.
How do you understand the cause of your relapse?
You understand the cause of a relapse by honestly reconstructing the situation: what happened, what triggered the consumption, and what function did it have at that moment? Assessors pay attention to this functional understanding, i.e. to what purpose drinking served for you and what it compensated for.
Helpful questions for working through it are:
- In what situation did it happen: stress, a party, conflict, loneliness?
- Were there warning signs beforehand that you overlooked?
- Which strategy would have worked, and why did it not work this time?
- What are you specifically changing so that this situation turns out differently next time?
A relapse can also be a sign that more support is needed. In cases of dependence or repetition, traffic therapy (Verkehrstherapie) is intended as more intensive, longer support.
How do you restart properly?
You restart properly by first addressing the cause and then setting up the programme again without gaps. Only start abstinence again when you can really keep it up; another break costs time again.
- Record the relapse honestly: date, situation, trigger, for yourself and for your preparation.
- Work through the cause: on your own, in counselling (Beratung) or, if necessary, in therapy.
- Adjust your strategies: name risk situations and set out concrete emergency plans.
- Restart the programme: at a laboratory accredited under DIN EN ISO/IEC 17025 that is recognised by the assessment centre (Begutachtungsstelle für Fahreignung).
- See it through without gaps: keep your ID ready, attend appointments immediately, do not dye your hair if you are doing hair EtG.
You can find more about the requirements for a valid programme on the page about proof of abstinence.
How does a relapse change your schedule?
A relapse pushes back your schedule by the length of testing you have already completed, because the required period of 6 or 12 months begins again. With urine screening, this again means 4 tests for 6 months or 6 tests for 12 months. The abstinence period is usually the bottleneck of the whole plan anyway.
If you have already applied for the reissue of your licence (Neuerteilung), or if a deadline set by the authority is running, the restart can become tight in terms of time. In that case, clarify early how to proceed, and for legal questions about deadlines consult a specialist lawyer for traffic law (Fachanwalt für Verkehrsrecht). The page on MPU deadlines gives an overview of deadlines.
What does restarting the abstinence programme cost?
A restart costs you above all money for the additional tests that you have to pay for again. As guideline values for 2026, a urine sample costs about €60–120 and a hair sample about €120–200. A complete programme costs about €200–900, depending on duration and method.
Factor this sum realistically into your planning. This is another reason why it is worth only tackling the restart once you have understood the cause and can really keep up abstinence.
What you can do now
- Stay calm and cover nothing up: a relapse is not the end, but a reason for honest reflection.
- Contact the laboratory immediately if it is about a missed appointment, and clarify where you stand.
- Understand the cause with professional support. Find suitable preparation.
- Draw up a new schedule: restart date plus 6 or 12 months, then plan your application and the MPU.
- Avoid EtG traps: if in doubt, leave out food containing alcohol and mouthwash; more on this in the guide EtG test, food and mouthwash.
Frequently asked questions
Do I have to mention a relapse in the MPU interview?
A concealed relapse that comes to light later costs you all your credibility. Assessors compare lab values, the file and your account, so it is wiser to assess a relapse honestly and show what you have learned from it and changed.
Can I still pass the MPU at all after a relapse?
Yes, a relapse is not the end of the road. However, it pushes back your schedule because the testing period begins again, and you should work through the cause thoroughly.
Can mouthwash cause a positive EtG value?
EtG can also test positive because of food containing alcohol or mouthwash. That is why the rule during the programme is: avoid such products if in doubt.
How long can alcohol be detected in urine?
The marker EtG can be detected in urine for about 24–80 hours. That is why appointments are given at short notice and unannounced.
