What causes a fishy, foul odor in urine?

Urine with a fishy or foul odor may be caused by dietary factors, dehydration, urethritis, nephritis, diabetes, and other reasons. It is recommended to seek medical attention promptly, identify the underlying cause, and receive appropriate treatment under the guidance of a healthcare professional. Specific causes are analyzed as follows:

1. Dietary factors: Consuming foods with strong odors such as asparagus, onions, and garlic may affect the smell of urine after ingestion, leading to a fishy or unpleasant odor. It is advisable to adjust eating habits and reduce intake of these foods to help alleviate symptoms.

2. Dehydration: Insufficient fluid intake can lead to reduced urine volume and increased urine concentration, which may result in a stronger, foul-smelling urine. Increasing daily water intake helps maintain adequate hydration, dilute urine, and reduce both its concentration and odor.

3. Urethritis: This may be related to mechanical irritation, frequent late-night habits, and other factors. These conditions may promote bacterial growth in the urethra, where bacteria break down metabolic substances, causing urine to develop a foul odor. Patients should follow medical advice and take medications such as azithromycin granules, cefixime granules, or roxithromycin tablets as prescribed.

4. Nephritis: This condition may be associated with poor dietary habits, lack of physical activity, and other factors. Impaired kidney function may hinder the effective elimination of metabolic waste and toxins through urine. Accumulation of these substances in urine may lead to a foul odor. Patients should follow medical instructions and use medications such as valsartan-hydrochlorothiazide tablets, acetic acid prednisone tablets, or dexamethasone tablets as directed.

5. Diabetes: Typically caused by sedentary lifestyle and high-fat diet, poorly controlled blood sugar levels can lead to excess glucose and ketones in the urine, resulting in a distinct, foul odor. Patients should use medications such as insulin aspart injection, insulin degludec injection, or orlistat capsules under a doctor’s supervision to manage their condition.

In daily life, patients are encouraged to engage in moderate physical activities such as walking or playing badminton, maintain sufficient sleep, avoid staying up late, and follow a low-sugar diet, all of which are beneficial for recovery.