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All information on drugs

At a glance

A drug test proves the use of drugs .

Most drug tests are performed with urine because urine is easier to obtain than a blood sample.

A test usually takes place in two steps. An initial preliminary test is carried out to check whether a substance has been taken. If this first test is positive, the post-test is used to secure the result and determine the quantity.

A distinction is also made between more complex laboratory tests and so-called rapid tests, which can be carried out on site.

Further information

Quantitative drug testing determines not only the type but also the amount of a substance. If you don’t know what kind of drugs to test on beforehand, so-called drug screening helps.

In this case, the most common substance groups such as alcohol, cannabis and opiates can be qualitatively proven by a multiple test in one step. A positive test result does not necessarily mean that someone has deliberately used drugs. Some medicines or even foods, such as baking poppies, can make a test for opiates positive.

In order to determine whether a positive test result can actually be regarded as evidence of a (intentional) substance intake, the so-called cut-off value is determined. The cut-off is considered a limit value. If this value is exceeded in the sample, active drug use can be assumed.

However, drug tests are not only carried out to prove possible misconduct. Detection in medical emergencies can also be important. In this way, important steps such as the administration of an antidot or emergency ventilation can be initiated immediately.

Reasons for a drug test include:

  • Poisoning and emergency situations
  • Follow-up control in drug withdrawal therapy
  • Clarification of the question of guilt, for example in the case of road accidents
  • Investigations in forensic medicine

Drugs most commonly tested in urine are:

  • Ecstasy – Amphetamines/MDMA (about 3 days detectable)
  • Benzodiazepines (detectable for 2-10 days, depending on strength)
  • Cocaine/crack (about 3 days detectable)
  • Metamphetamine -Meth/Crystal (approximately 3-5 days detectable)
  • Morphine (heroin) / opiates (approximately 2-7 days detectable)
  • Cannabinoids (approximately 3-7 days detectable, detectable with frequent use for months)

In order to avoid counterfeiting of drug tests, so-called marker solutions are often used. These must be drunk about 30 minutes before the urine sample is taken and then later can be found in the urine sample. This is to prevent the unnoticed delivery of foreign or artificial urine.


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Status of information: 2022