False-Positive Results in 5% to 10% of Cases
To get a better picture of the tests' flaws, Smith and colleagues at Boston Medical Center reviewed scientific articles on drug screening published between January 1980 and September 2009.
The results were presented at the American Psychiatric Association's annual meeting.
Cold
medications, the
antidepressant Wellbutrin, and tricyclic antidepressants can trigger false-positive results on tests for
amphetamines, according to the review, and the antidepressant Zoloft and the painkiller Daypro can show up as a benzodiazepine problem.
The quinolone antibiotic drugs can trigger false positives for opioids, and the HIV medication Sustiva can show up as
marijuana use, Smith says.
On the other hand, just being in the room with someone who is smoking marijuana is not going to trigger false positive results, no matter what your child claims, he says.
"Unless [they] were in the van with Cheech and Chong, that's not what happened," Smith says.
And "cocaine is cocaine -- you don’t get many false positives or false negatives," says Petros Levounis, MD, director of the Addiction Institute of New York at St. Luke's and Roosevelt Hospital in New York City.