False Negative Result Urine. Some potential explanations for why a prescribed drug might not be detected in a patients urine sample include medication hoarding or diversion the time between last dose and sample collection self-escalation or binge use failure to take the medication or taking only as needed rapid metabolism drug-drug interaction and potential lab error. In early pregnancy you can dilute the hormone concentration in your urine if you drink a lot of water before testing.
Jun 13 2009 - 14 comments With all the posts inquiring about false negative urine test I wanted to put this in my journal for reference. Urine samples can be adulterated with other substances to mask positive results on urine drug testing. Some potential explanations for why a prescribed drug might not be detected in a patients urine sample include medication hoarding or diversion the time between last dose and sample collection self-escalation or binge use failure to take the medication or taking only as needed rapid metabolism drug-drug interaction and potential lab error.
This is more likely to happen in very early pregnancy when you take the test later in the day.
These terms are inadequate because they are used in different ways by physicians and laboratory professionals and they are too narrow to encompass the larger universe of potentially misle. Diluting the urine can spread out the presence of hCG and make it too low for the test to read giving you a false reading. In early pregnancy you can dilute the hormone concentration in your urine if you drink a lot of water before testing. When this issue comes up I always have to research the information so it is easier to just add it here in my journal.