False Positive Results on Drug Tests for Employment

• Drug testing plays a common role in the hiring process. Jupiterimages/Comstock/Getty Images

  Drug testing is a common element of the employment process. Upon taking a position, many employers require some form of testing. Others reserve the right to test you at any point. Employees often fear a false positive result -- but there are ways to prevent this outcome and ensure your employment status remains safe.

Secondhand Use

• Secondhand exposure to illegal narcotics is an old concern that contains some fact and myth. While secondhand exposure to some smoked narcotics is possible, the level of exposure required to surpass the minimal use guideline is quite high. Hair tests have an increased likelihood of returning a positive test through passive exposure due to the lack of filter between the exposure and your hair. Other forms of narcotics such as cocaine and heroin have an increased likelihood of a false positive due to passive exposure and their resilience once they come in contact with your hair. Employee drug testing prefers urine testing to hair tests in order to reduce cost. This is a benefit to you in regards to secondhand use where urine testing is less likely to return a false positive.

OTC Medicines

• Over the counter medicines such as Ibuprofen, Midol, Nupren and Sudafed can generate false positives for marijuana use, according to College Grad. More recent tests are better able to distinguish between the two chemicals. This is no longer a concern regarding false positives. If you are being tested outside the United States, this is still an area of concern and could lead to trouble. Drug testing is improving everywhere -- but some countries are not yet using the most advanced testing methods. If you are taking a drug test for employment in another country, check with the specifics behind their drug testing procedures and let your tester know of any medicines you're taking, both over the counter and prescribed.

Poppy Seeds

• Minute amounts of morphine exist within poppy seeds. However, the quantity of seeds required for a sustained false opiate positive is extremely high. A small quantity of poppy seeds eaten on the day of your drug test can generate a false positive for that day. Repeated use of poppy seeds over an extended period yields a false positive through hair tests. The false positive generated from eating a small quantity of poppy seeds will go away a day after consumption with normal dieting and rest to give your body time to metabolize the seeds. Avoid eating poppy seeds for more than 24 hours prior to the time that you expect to be tested.

Retest

• If your drug test does reveal a positive and you have not used any illicit narcotics recently, you have the right to request an additional drug test at a later date. Many employers are unwilling to pay for this additional test and these more precise tests are often performed through hair tests rather than urination tests.