Im currently taking mastic gum and dgl. im planning on doing urea breath test for h pylori in a few weeks. will these supplements interfere the test?

Not exactly but...: Mastic gum is an effective treatment for H. pylori so hopefully it will eliminate H. pylori overgrowth from your stomach. Thus, taking it should significantly reduce the chance of the test being positive. In that sense it may "interfere" with the test by curing you before the test, but won't result in inaccurate results. If the test is still positive it will suggest you need additional treatment.

Best to stop them...: While the data on mastic gum and DGL is limited, and while the American Gastroenterological Association does not endorse them as treatments for H pylori, they can potentially interfere with the test. If the mastic gum kills some but not all of the H pylori, this may result in a "false negative" test. In other words, the test may state you don't have H pylori but in fact you still do.