What causes false positive for Benzodiazepines?

look for "livingstrong.com -drugs that can cause false postive drug test" you will be suprised what all shoes up inncorrect,my seroquel xr says on the information pamblet that it will show up methadone, on the web site i just gave you it says for zoloft can show up benzos,acid reflux meds can show up marijua,antibiotics can show up for cocaine