There are three primary types of drug sample : blood, urine, and hair. Most common is the urine test which has the benefit of being inexpensive and less intrusive than the blood test.
? Are the least expensive of the test methods (~$25-$50).
? Can be done at home (for example by parents).
? Detect use primarily within the past week (longer with regular use).
? Can be affected by abstaining from use for a period of time
before the test.
? Are often temperature tested to insure sample integrity.
? Are considered the least intrusive method of drug testing.
? Are currently many times more expensive than urine tests (~$100-$150).
? Detect substance use over a longer period (see detection times).
? Do not usually detect use within the past week.
? Require a sample of hair about the diameter of a pencil and 1.5 inches long. They can not be done with a single hair.
? Test positive a little more than twice as often as a urine test. In a recent study, out of 1823 paired hair and urine samples, 57 urine samples tested positive for drugs of abuse; while 124 hair samples from the same group tested positive.
? Are not significantly affected by brief periods of abstinence from drugs.
? Can sometimes be used to determine when use occured and if it has been discontinued. 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 migrate along the shaft; making it very difficult to determine when the drug was used and for how long.
? Claims to be able to reliably differentiate between opiate and poppy seed use.
? Are considered the most intrusive method of testing.
? Are the most expensive method of testing.
? Are the most accurate method of testing.
? Are the least common method of testing (most likely due to cost).