Good afternoon, I am a psychologist doing an eval on a client who tested positive on a UA for cocaine. She repeated the test and was negative. The client takes Omeprazole. I am researching to determine if this med. can give a false positive on a UA. I have learned that Omeprazole can test false positive for THC. Do you know of a research article or website that supports any of this - although it is not cocaine. -Charlotte