 [ Symptoms ] i have been prescribed euthyrox and dostinex for infertility need second opinion [ Disease ] no just the thc will cause a positive result and can remain in the system for quite a 2 3 weeks omeprazole is not even close to the chemical structure of thc there can be false positive drug tests but those are rare assuming it was tested at a good lab webmd is incorrect in this instance i know for a fact that omeprazole and all ppi is proton pump inhibitors can most definitely cause a false positive for thc this is from several physicians my own pain management doctor for one and a relative who works for a testing firm that does drug testing for the federal government yes prevacid or omeprazole can cause a false positive for thc i tested myself at home in the a m and was negative for thc i tested for the court in the p m after taking omeprazole prilosec and tested positive for thc i called the company first check that makes the home test they told me pantoprazole can cause a false positive but could not say for sure if omeprazole would cause a false positive they recommend any positive test be mailed to them for mass spectometry testing which could rule out a false positive twice i was jailed for testing positive and then was released after testing negative the next day when i had not taken omeprazole only one time have i tested positive for thc at my pain clinic i was extremely embarrassed and shocked i am 52 years old and have not smoked pot since i was 19 i had just started a trial of omeprazole which my provider asked me about by name i switched to another acid reducer at her suggestion and had no more problem now i have done the rounds with these medications and it looks like omeprazole is all that is left hopefully they will be reasonable i have ulcerative colitis and gerd