A nurse preparing to administer a dose of the anti-infective drug metronidazole scanned a bar code at the top of the I.V. minibag label, and the scanner screen read levothyroxine, a thyroid hormone. She then scanned the bottom bar code, which is used for billing, and the scanner screen indicated metronidazole.
When the nurse carefully inspected the top bar code, part of the label had apparently been ripped as if it had been removed and reapplied unevenly. This created a new bar code that happened to read as levothyroxine.
If a label is ripped, pharmacy should print a new one. If you get a bar-code label that isn't intact, return the drug to pharmacy.