Drug Testing For Cocaine

There are several methods of drug testing for cocaine including hair, urine, blood and saliva. Many employers require drug testing before hiring employees, which screens for cocaine, marijuana, amphetamines, PCP and opiates. Failure to pass the drug test results in withdrawal of the job offer. The only sure way to pass the drug screening is to avoid illegal drugs.

The time of day the testing is done can affect the results of the test. A specimen of urine first thing in the morning gives the highest concentration of drug metabolites. Tests taken throughout the day can vary, just as the concentration of the urine varies. Some people drink a lot of water to try to dilute the concentration of their urine to avoid a positive result. In the work setting, the best way to get a representative sample is to test randomly.

How long cocaine remains in the system can also vary. The average is three to five days, but depending on your metabolism, weight and amount of cocaine you have used, there is no set amount of time. Some studies say people who use high dosages can test positive after eight days, while other studies claim it can be detected after ten to fourteen days and with really high usage from ten to 22 days. People who are heavy often have a slower metabolism and it may take longer to leave the system, while people who are skinny often have a quicker metabolism, which allows the drug to leave their system sooner.

There are several ways testing can be done to determine the presence of cocaine. The urine test screens for benzoylecgonine, which is a metabolite of cocaine, and measures how much is in the sample. A reading of 300 micrograms per liter or more is considered a positive result. If the first test is positive, a second type of screening may be done and a reading of over 150 micrograms per liter determines positivity. Urine tests do not determine whether the person is under the influence, only if they have the drug in their system. It is the most inexpensive and common type of testing.

Blood testing can determine whether the person is under the influence and it is the most accurate. This is the most invasive test and must be done in a laboratory. It is also the most expensive test.

Testing can also be done using a hair sample. The hair should be at least 1.5 inches from the scalp and about the diameter of a pencil. This test is more expensive than a urine test and easily detects the presence of the drug. It can detect cocaine use up to 90 days, but it cannot tell when the drug was used or for how long.

Saliva can also be used to test for cocaine for up to 24 hours after use. This method is less expensive than blood or hair testing and easier to administer. It must be sent to a laboratory for analysis. The results may vary depending on the brand of test used, which could possibly make this test less reliable.

If you are required to get a drug test for your employment, it is important that proper collection and testing procedures are used. Collection should follow certain procedures, such as proper marking of the container and a temperature between 96 to 99 degrees to prevent samples from being tampered with. Improper marking or tampering of the label of the container is one of the biggest causes of unreliable testing. If your results are positive, be sure that a second analysis is done to make sure it is not a false positive. A study of 161 prescription drugs and OTC medications showed than 65 of these drugs produced false positive results in urine tests. Remember, if you have taken any of the following drugs or have any of the following conditions, they can cause a false positive for cocaine: kidney infection or kidney disease, liver infection or liver disease, diabetes, amoxicillin or tonic water.