How to Interpret Drug Tests

A urine sample is the most common specimen used to test for the presence of drugs. Amphetamines, barbiturates, benzodiazepines, cannibinoids, cocaine, opiates and phencyclidine (PCP) are the seven drug classes that are most commonly screened for. Doctors order drug testing on patients displaying signs of substance abuse, mainly to decide on the proper treatment. Employers and legal entities use drug testing primarily to determine the presence of illegal drugs.

Instructions

• 1

  Search your laboratory report for the terms "positive" or "not detected." Every lab decides on a cut-off value for each drug class. Any result above the established cut-off value is considered positive, and any value below it is considered negative. In your lab report, every drug class tested has a "positive" or "not detected" result next to it.

• 2

  A positive screen for a drug class indicates the presence in the body of a substance belonging to that drug class at a concentration higher than the established cut-off.

• 3

  Each drug class that tests positive in the drug screen generally is further examined to determine the specific drug or drugs used. Some over-the-counter drugs and legally prescribed medications can cause a positive result. Always declare any medications you have taken and have prescriptions for when you have a drug test.

• 4

  Know that a "non-detected" result for a drug class doesn't necessarily mean that the person tested did not use drugs at some point. The drug or drugs may be present at levels below the established cut-off value because they have already been metabolized and secreted from the body. Amphetamines, cocaine and opiates read positive only if used in the two or three days preceding the sample collection.