A drug test is a test procedure that is usually carried out on the basis of suspicion of substance misuse and serves to determine the quantity and type of the active substance (drug, medicine, etc.) absorbed into the human organism. Suitable examination materials include blood and saliva, in which the administered substances accumulate after only a few minutes, urine and sweat, which contains detectable concentrations after a few hours, as well as hair and nails, in which the active substances are incorporated after several days.
Testing can be carried out either in the form of rapid tests (test strips, etc.) or laboratory tests (antibody detection with an immunoassay such as ELISA, chromatography, mass spectrometer). Among the detectable drugs are : Alcohol, cocaine, cannabis, stimulants such as amphetamines or ecstasy, barbiturates, opioids, hallucinogens such as LSD or K. O. drops (gamma-hydroxybutyric acid).
Drug test based on blood
Blood, as the medium transporting the addictive or drug substance, is one of the most suitable test materials, as it is responsible for transporting the substance to the organs or sites of action from the time of administration until it is completely excreted or completely broken down. However, it is important to know that drug substances or their degradation substances are present in the blood in much lower concentrations than, for example, in urine. This means that the drug intake can only be detected for a comparatively short time (hours to a day) before the active substance is broken down to such an extent that its concentration can no longer be determined by the usual tests.
A general screening for substance misuse is therefore only possible to a limited extent. On the other hand, the blood is all the more suitable for assessing the direct substance-mediated influence on the person concerned, e.g. through the intake of alcohol, drugs or medicines. The only disadvantage of a blood sample collection that is necessary for this purpose is that it is an invasive procedure.
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