I have an issue with urine test, and seek advice what can a person do to clean up in preparation for a test

First : First of all, if you haven't partaken in any illicit drug use or alcohol consumption, then you need not worry about a urine screening test. However the sensitivity and length of time one must be "clean" varies depending on the agent being tested. The etg test is sensitive to the presence of any alcohol, even low-levels, and can detect alcohol in the urine several days after consumption. But the test is so sensitive, it can produce a positive test for ethyl glucoronide from the mere exposure to alcohol that is present in many daily use products. Substance urine alcohol tests may measure etg which can stay in urine for up to 80 hours amphetamines (except methamphetamine) 1 to 5 days methamphetamine 3 to 5 days mdma (ecstasy) 72 hours barbiturates (except phenobarbital) 1 day phenobarbital 2 to 3 weeks benzodiazepines therapeutic use: up to 7 days. Chronic use (over one year): 4 to 6 weeks cannabis 2 to 7 days, up to >30 days after heavy use and/or in users with high body fat cocaine 2 to 5 days codeine 2 to 3 days cotinine (a break-down product of nicotine) 2 to 4 days morphine 2 to 4 days heroin 1 to 4 days lsd 12 to 24 hours methadone 3 days pcp 3 to 7 days for single use; up to 30 days in chronic users.

Assuming : Assuming you are not abusing illicit drugs or medications that were not prescribed for you, there shouldn't be cause to worry. If you are taking a medication that was prescribed for you that may trigger on a urine drug screen you can normally obtain a memoradum from your prescribing provider or bring in the prescription container as proof that there is a legitimate reason for a positive test result. However, if you are under a pain contract, and have obtained a prescription, from an outside source, that will likely be of no help.