You should not take a urine test after taking the medication, because taking the medication may affect the accuracy of the urine test results. After taking vitamin B1 urine is yellow, the doctor from the physical shape of the urine will be subjective judgment that there is a certain amount of jaundice, which will cause difficulties for the doctor’s judgment, but also to check a liver function, which will cause difficulties for the doctor’s correct diagnosis, so the urinalysis must be avoided before the medication. Three days before the urine test to avoid taking specific drugs, such as diabetic patients to eat glucose-lowering drugs (metformin, carboplatin), hypertensive patients to eat antihypertensive drugs (hydrochlorothiazide, dihydrochlorothiazide, etc.), which will affect the accuracy of the results of the urine test. Due to the different causes of the disease, different medications do not have the same effect on the accuracy of the urine test, please follow your doctor’s instructions for specific cases.