How Does Drug Testing Work?

Drug testing is a common procedure, and many people feel the need to obtain a drug test for many different reasons and circumstances. It is important to know how the process works before you acquire a test, to ensure you understand what it consists of and your role within the procedure. A drug test is performed to detect whether or not a person has previously used or currently using any illegal or toxic chemical compound. Here are some examples of why you may acquire a drug test:

  • Sports Event
  • Job Interview
  • Legal Matter

Sample Collection

The process begins with collecting a suitable sample to perform the test. Any negligence in the sample collection may lead to a false-negative or false-positive. It is all because of the half-life of the drug.

Every drug has a specific life span in the body; if you take the sample after the specific time frame when the drug has been eliminated in the body, the test may not provide you with the most accurate result. Hence, depending upon the drug for which the test is conducted, its half-life should be known first. Other contributing factors may be age, sex, and weight, which could be considered before taking a drug test.

Here are some of the samples that can be used for the test:

  • Urine
  • Blood  
  • Sweat
  • Oral fluid
  • Hair

 Mechanism Of The Test

Even though there are many samples that can be collected in order to perform a drug test, there are two specific techniques used to detect the presence of the drug: ELISA and Chromatographic technique.

ELISA (enzyme-linked immunosorbent assay) uses antibodies against foreign agents for detection. The chemicals are identified by adding the labelled antibody to the drug solutions micro-well. Afterwards, the optical density is measured using a spectrophotometer. If the chemical is specific to the drug, it will make a complex and hinder light passing of a particular wavelength.

For the chromatographic technique, the chemicals are separated based on their molecular weight and size. Gas chromatography is generally preferred for drug tests.

Home Kits

If you are not willing to give a sample or simply don’t have time, you can take a more rapid route. This includes diagnostic kits available on the market to carry out at home. These test kits will provide speedy, accurate results. The chemical reagents are added in those kits; therefore you do not have to worry that you are not experienced in that field.


The mechanism of drug testing is reliable and straightforward. Whether you choose to visit your doctor’s office to acquire one or carry out an at-home test kit, you can assure your results are accurate. Regardless of the reason for your test, there is a method of testing to suit you.