The color of urine turns dark brown after a long time

It is normal for urine to turn brown after being stored for a long time, because long-term urine is easy to deteriorate under oxidation. If you want to use urine to do related tests, there is a time limit. Normal urine should not be stored for more than one hour, otherwise it will affect the results of the test. The storage time of urine is also related to changes in temperature. For example, the higher the temperature, the longer it can be stored. If the temperature of urine is low, it can be stored for more than an hour. Morning urine can be taken for examination when checking. Morning urine is not diluted. The effect of examination is more accurate.