Saliva analysis and blood test for drugs in Belgium: counter-analysis and costs

The quick saliva test at the roadside gives an indication, but not legal proof. That proof comes from the saliva analysis or the blood test that follows. For your defence, these later steps are therefore the most important: that is where the thresholds are measured, where strict rules apply and where you are entitled to a counter-analysis (contre-expertise), within a short deadline.

This article is part of our overview of drug driving.

The saliva analysis

After a positive saliva test, the police take a second saliva sample for laboratory analysis (article 62ter of the Road Traffic Act (loi relative à la police de la circulation routière)). The rules are set out in the Royal Decree of 27 November 2015. Among other things, it governs the sampling kit, the working method, the analysis method and the approval of laboratories.

How it works

• The sampling kit comes in a sealed package, with instructions in the three national languages and adhesive labels bearing a unique identification number.
• You collect the saliva yourself with a collector placed under your tongue.
• The collector stays in place until an indicator turns blue, or until five minutes have passed. In both cases, the sample is valid.
• The sample is sealed and sent to an approved laboratory.

For the saliva analysis, only one type of sampling kit is authorised. Other kits may not be used.

The thresholds

The laboratory measures whether the legal thresholds are reached. They are lower than for the quick test:

Substance	Saliva analysis (ng/ml)	Blood analysis (ng/ml)
THC	10	1
Amphetamine	25	25
MDMA	25	25
Morphine or 6-acetylmorphine	5	10
Cocaine or benzoylecgonine	10	25

If the value stays below the threshold, you are not committing an offence, even if the saliva test was positive.

The shortage of collectors

Between the end of 2025 and September 2026, there was a shortage of saliva collectors, because the previous supply contract was coming to an end. During that period, the police more often had a blood test carried out. From September 2026, new collectors are being brought into use. If your case concerns events from that period, it is worth checking which procedure was followed and whether it was the right one.

The blood test

A blood test follows when the saliva test is positive but the saliva analysis cannot be carried out, or when neither is possible (article 63 of the Road Traffic Act).

Who takes the blood sample?

• Any member of the police’s operational staff can call in a doctor.
• You have the right to be assisted, at your own expense, by a doctor of your choice. This may not delay the procedure.
• The blood sample itself can be taken by your treating doctor or your GP. It is a purely technical procedure.
• The clinical report can never be completed by your own doctor or your treating doctor. If it nevertheless is, that report is void for lack of objectivity.
• A doctor called in who refuses to cooperate can himself or herself be prosecuted.

How is the sample taken?

Only the equipment provided by the police may be used. The blood is drawn directly from the vein, in a medically appropriate way. The doctor may insert the needle more than once, but force is never allowed.

The result and the counter-analysis

As a rule, you are informed of the result of the saliva or blood analysis within 45 days. From the moment you receive it, you have 14 days to request a counter-analysis (for the saliva analysis: article 62ter, § 4 of the Road Traffic Act). This counter-analysis is carried out on the same sample.

This 14-day deadline is short. Anyone who leaves the letter lying around loses the opportunity to challenge the result on the substance. The result of the analysis counts as legal proof, and it is then much harder to cast doubt on it.

A counter-analysis is particularly useful if the level measured is close to the threshold, if you have doubts about the identification of the sample or if, in your view, the drug use was a long time before. Get advice without delay.

Who pays?

If the offence is established, you pay the costs of the saliva test, the saliva analysis, the blood test and the doctor called in, as legal costs. A higher rate applies for a doctor’s services at night, at the weekend or on a public holiday. If it turns out that you did not commit an offence, or if you were involved in an accident but were neither the driver nor the person accompanying a learner driver, the costs are borne by the State.

Refusal

Refusing the saliva analysis or blood test without a legitimate reason is an offence (article 37bis, § 1, 5° of the Road Traffic Act). The police then always call in a doctor, who assesses whether there is a legitimate reason. Someone who genuinely cannot produce enough saliva is not refusing. Also see our article on refusing a test.

What does the defence look out for?

• Was the correct sampling kit used, and was the package sealed?
• Is the identification of the sample correct on all documents?
• Was the clinical report completed by an independent doctor?
• Was the result communicated on time, and were you informed about the counter-analysis?
• For events during the shortage of collectors: was the correct procedure followed?

An error does not automatically lead to the evidence being excluded. The judge assesses whether the reliability of the result or your right to a fair trial has been affected. See our article on errors in the police report (procès-verbal).

Frequently asked questions

Have your case reviewed

Have you received a result and do you have doubts? Contact us quickly, so that the deadline for a counter-analysis does not expire. Contact us.

Law as at 28 September 2026. We update this article when the rules change.