Can you use expired urine strips?
Do not use the Urine Dipsticks and Urine Controls after the expiration date.
What causes false negative drug test?
False-negative results occur when a drug or metabolite is present at such low levels that it is not detected. Confirmatory testing is essential to distinguish a true negative from a false negative. Contaminants can also interfere with the immunoassay’s ability to detect the presence of drugs.
How long is urine valid for a drug test?
If you can’t hand your urine sample in within 1 hour, you should put the container in a sealed plastic bag then store it in the fridge at around 4C. Do not keep it for longer than 24 hours. The bacteria in the urine sample can multiply if it is not kept in a fridge. If this happens, it could affect the test results.
Can pH strips expire?
If preserved using our buffer preservative and stored properly, they last up to 3 months. pH papers – 3 years. The expiration date is marked on the color chart.
Can you fight a failed drug test?
Urine drug screens are the most common test, although other body fluids may be analyzed as well. Many commonly used substances can trigger a false-positive test result. If you’re certain that the result is false, immediately take action and dispute false-positive results.
What is a positive drug test?
If your results are positive, it means one or more drugs were found in your body above an established level. However, false positives can happen. So if your first test shows that you have drugs in your system, you will have further testing to figure out whether or not you are actually taking a certain drug or drugs.
What happens to urine when refrigerated?
Refrigeration can result in the precipitation of urates or phosphates, which may obscure other pathologic constituents in the microscopic examination of the urine sediment. According to NCCLS, If the urine is also to be cultured, it should be refrigerated during transit and held refrigerated until cultured.
When do test strips expire?
Test strips are effective for either 3-4 months after opening or until the expiration date if sealed and unopened. After opening a test strip vial, make sure to tightly close the lid again to prevent the ingress of humidity.