A drug is any substance that, when absorbed into the body, changes normal bodily function. In pharmacology, it is “a chemical substance used in the treatment, diagnosis, cure, or prevention of disease or otherwise it is used to augment physical or mental well-being”. Drugs may be prescribed for a limited duration or on a regular basis for chronic disorders. There are also some drugs that can cause habituation and addiction. Drugs can be managed in a number of ways whether it’s recreational or medicinal one by means of technical examination of whether urine, sweat, blood, oral fluid, or even hair samples. This is referred to as drug test or drug screening. It determine the presence neither the absence of specified drugs nor even their metabolized traces.

There are primary types of drug tests: urine, blood, hair, saliva and sweat. The most common is the urine test which has the benefit of being inexpensive and less intrusive than the blood test.

Urine Tests are the least expensive of the test methods and are considered as an intrusive method of testing. These can be done at home though need lab verification for accurate results. Also, detect use primarily within the past week (longer with regular use) that can be affected by abstaining from use for a period of time before the test. These tests are often temperature tested too to assure sample integrity. Saliva Tests are a little more expensive than the urine testing, but less than hair or blood tests and considered a relatively undisturbing process of drug testing. These are becoming more common because these kinds of test are easy to manage but require lab processing to guarantee accuracy. One can detect use first and foremost within the past few days and can detect more recent use than other testing methods. Such tests also have no nationally accepted standards or cut off concentrations for detection, making results greatly reliant on the specific product purchased. This could also make results less-reliable or acceptable for legal cases. Not to mention such tests are more reliable for detection of Methamphetamine, Opiates and less reliable for THC or Cannabinoids. Hair Tests are currently several times more costly than the urine tests and considered a relatively unintrusive manner of drug testing. These detect substance use over a longer period and do not usually identify use within the past week. Drugs, such as opiates (codeine, morphine, heroin) lay down on the hair shaft very tightly and are shown not to migrate along the shaft, thus, if a long segment of hair is available one can draw some “relative” conclusions about when the use occurred. However cocaine, although very easy to detect, is able to drift along the shaft; making it very difficult to determine when the drug was used and for how long. Blood Tests are the most expensive and common way of testing among the rest. Not to mention that these are the most meddling method of testing and most accurate one. Sweat (Patch) Tests are deemed relatively intrusive means of drug testing because these require the wearing of a patch for an extended period of time. They are controversial in terms of accuracy for some reason to consider that surface contamination (such as cannabis smoke) can cause a false reading. Also, such tests can detect use which would not prompt other tests. Because of the short detection period for many drugs in urine, single use of many drugs longer than a week prior to using the patch will not cause a positive urine test. Since the skin patches are gathering sweat over an extended period of time, it is possible that any use during that time will turn out a positive outcome.