What changes occur in urine after taking metronidazole?

Urine may become darker in color after taking metronidazole. The specific analysis is as follows:

Metronidazole is a commonly used anti-inflammatory medication in clinical practice, with bactericidal and anti-inflammatory effects. It is used to treat diseases caused by infections of the urinary or respiratory systems. After oral administration, metronidazole tablets are absorbed into the body and metabolized through the liver, which may cause urine to turn brownish. This is generally a normal reaction associated with drug metabolism, and once the drug has been fully eliminated from the body, urine color typically returns to normal. This phenomenon is considered benign and does not require special treatment.

However, if a patient has a concurrent urinary tract infection while taking metronidazole, inflammation may irritate areas such as the bladder and urethra, leading to local congestion, edema, and even rupture of capillaries, resulting in hematuria. Blood in the urine can give it a tea-colored appearance, often accompanied by urinary irritation symptoms such as frequency, urgency, and dysuria. Urinalysis would typically show significantly elevated red and white blood cells.

In addition, urinary system stones or tumors may also cause darkening of urine after taking metronidazole or other medications, and prompt medical evaluation and treatment are necessary in such cases.