Why is urine very yellow after COVID-19, and what should be done?

“Post-COVID” refers to infection with the novel coronavirus. Generally, dark yellow urine after infection with the novel coronavirus may be caused by insufficient water intake, prolonged urine concentration, urethritis, cystitis, gallstones, and other reasons. Symptomatic management through general measures or medication is required. If discomfort occurs, it is recommended to seek medical attention promptly and receive appropriate treatment under a doctor's guidance. Specific analyses are as follows:

1. Insufficient water intake: After infection with the novel coronavirus, the body may experience symptoms such as fever, sweating, and sore throat. These symptoms increase fluid loss from the body. Without timely replenishment of adequate fluids, the kidneys produce less urine, leading to relatively higher concentrations of metabolic waste in the urine, resulting in darker yellow urine. It is recommended to increase fluid intake according to sweating levels and other fluid losses.

2. Prolonged urine concentration: After infection with the novel coronavirus, some individuals may reduce urination frequency due to physical discomfort, such as prolonged bed rest. When urine remains in the bladder for extended periods, more water is reabsorbed, causing relative concentration of various components in the urine and resulting in a darker yellow color. It is recommended to urinate at regular intervals—even without a strong urge to urinate, one should attempt to void every few hours.

3. Urethritis: After infection with the novel coronavirus, reduced immunity may allow pathogens like bacteria to invade the urethra and cause urethritis. Inflammatory irritation leads to congestion and edema of the urethral mucosa, producing secretions. These secretions mix into the urine, and metabolic changes during inflammation may also alter urine composition, resulting in yellowish urine. It is recommended to use medications such as levofloxacin tablets, Sanjin tablets, and sodium bicarbonate tablets under medical supervision.

4. Cystitis: During novel coronavirus infection, bacteria may travel up the urethra into the bladder, causing cystitis. The bladder mucosa becomes inflamed due to bacterial infection, leading to congestion, exudation, and production of purulent secretions. These substances mix into the urine, causing it to appear yellow. Patients often experience symptoms such as frequent urination, urgency, and lower abdominal pain. It is recommended to take medications such as amoxicillin granules, erythromycin tablets, and cefixime capsules as directed by a physician.

5. Gallstones: Novel coronavirus infection may affect the hepatobiliary system, and some patients may develop gallstones. Gallstones can impair normal metabolism and excretion of bilirubin, which then enters the bloodstream and is filtered by the kidneys, eventually being excreted in urine, causing it to turn yellow. It is recommended to use medications such as ursodeoxycholic acid tablets, anti-inflammatory and bile-promoting tablets, and Dan Kang capsules under medical guidance.

After infection with the novel coronavirus, it is recommended to maintain a balanced diet, consume more fresh vegetables and fruits—such as oranges, spinach, and broccoli—to supplement vitamins and minerals, which helps strengthen immunity.