From the Guidelines
To treat low citrate in the urine, potassium citrate therapy should be offered to patients with recurrent calcium stones and low or relatively low urinary citrate, as it is associated with reduced risk of recurrent calcium stones. This recommendation is based on prospective RCTs, as stated in the AUA guideline 1. The guideline suggests that potassium citrate is preferred over sodium citrate, as the sodium load in the latter may increase urine calcium excretion.
Some key points to consider when treating low citrate in the urine include:
- Increasing fluid intake to produce at least 2 liters of urine daily
- Reducing sodium intake to less than 2,300 mg daily
- Consuming ample fruits and vegetables to counterbalance foods that confer an acid load
- Considering thiazides to lower urinary calcium excretion, which may increase the safety and efficacy of citrate therapy, as mentioned in the AUA guideline 1.
It is essential to note that potassium citrate supplements are typically prescribed at 10-30 mEq taken 2-3 times daily with meals, and the dose may be adjusted to minimize gastrointestinal side effects. Treating any underlying conditions like chronic diarrhea, inflammatory bowel disease, or renal tubular acidosis is also crucial. Regular follow-up with a healthcare provider is recommended to monitor urinary citrate levels and adjust treatment as needed.
From the FDA Drug Label
To restore normal urinary citrate (greater than 320 mg/day and as close to the normal mean of 640 mg/day as possible), and to increase urinary pH to a level of 6.0 to 7.0. Severe hypocitraturia (urinary citrate < 150 mg/day): therapy should be initiated at 60 mEq per day; a dose of 30 mEq two times per day or 20 mEq three times per day with meals or within 30 minutes after meals or bedtime snack Mild to moderate hypocitraturia (urinary citrate >150 mg/day): therapy should be initiated at 30 mEq per day; a dose of 15 mEq two times per day or 10 mEq three times per day with meals or within 30 minutes after meals or bedtime snack
The treatment for low citrate in the urine is Potassium Citrate. The dosage depends on the severity of hypocitraturia:
- Severe hypocitraturia (urinary citrate < 150 mg/day): 60 mEq/day, divided into 30 mEq two times a day or 20 mEq three times a day.
- Mild to moderate hypocitraturia (urinary citrate > 150 mg/day): 30 mEq/day, divided into 15 mEq two times a day or 10 mEq three times a day. The goal of treatment is to restore normal urinary citrate levels (greater than 320 mg/day) and increase urinary pH to a level of 6.0 to 7.0 2 2.
From the Research
Treatment Options for Low Citrate in Urine
- Dietary modifications can help increase citrate levels in the urine, including a high intake of fluids and fruits, especially citrus, sodium and protein restriction, with normal calcium intake 3
- Potassium citrate supplementation is effective in patients with primary or secondary hypocitraturia and acidification disorders, which cause unduly acidic urine pH persistently 3, 4
- Lemonade therapy has been proposed as a potential treatment for patients with hypocitraturia, with studies showing an increase in urinary citrate levels and a decrease in stone formation rate 5
- Other dietary interventions, such as commercial or homemade beverages, may also be effective in raising urine citrate levels, but further research is necessary to develop the ideal dietary therapy for hypocitraturic calcium nephrolithiasis 6
Mechanism of Action
- Citrate inhibits stone formation by complexing with calcium in the urine, inhibiting spontaneous nucleation, and preventing growth and agglomeration of crystals 7
- Potassium citrate restores normal urinary citrate, decreases saturation and propensity for spontaneous nucleation of calcium oxalate, and inhibits new stone formation 4
Efficacy and Safety
- Potassium citrate therapy has been shown to be effective in preventing new stone formation and reducing stone passage rate, with adverse effects being low and referred to the gastrointestinal tract 3, 4
- Lemonade therapy appears to be a reasonable alternative for patients with hypocitraturia who cannot tolerate first line therapy, with a significant citraturic effect and a decrease in stone formation rate 5