Naftopidil more effective than flopropione in helping to pass distal ureteral stones

This study compared two different drug therapies, naftopidil (Flivas) and flopropione (Cospanon), in improving kidney stone expulsion. Researchers reported a better stone expulsion rate and shorter time until expulsion with naftopidil compared to flopropione.

Kidney stones are small mineral deposits that can form in or near the kidneys. Kidney stones can be very painful and need to be passed or removed to avoid complications. Drug therapy can increase the chance of passing kidney naturally to avoid the need for surgical intervention. Alpha-blockers, such as naftopidil, work by relaxing muscles in the urine tract. Calcium channel blockers, such as flopropione, reduce muscle spasms and contractions in the urine tract. Both have been associated with improved spontaneous kidney stone expulsion (passing). However, more studies are needed comparing both drug therapies directly.

89 patients with kidney stones were randomly assigned to receive treatment with either naftopidil or flopropione. All patients had a single kidney stone (measuring 10 mm or less) located in the part of the ureter close to the bladder (distal ureteral stone). Treatment lasted until the stone was passed or for up to 28 days.

The average time until stone expulsion was 8 days for the group receiving naftopidil. This was significantly shorter than 18 days observed with flopropione. 77.5% of patients receiving naftopidil passed their kidney stone. In contrast, only 59.1% of patients receiving flopropione passed their kidney stone. Overall, the stone expulsion rate was 78% higher with naftopidil. This analysis accounted for age, gender, stone in side of body, and size of stone.

29.6% of patients in the flopropione group and 17.8% of patients in the naftopidil group required pain treatment after passing the stone. No hospital admissions were noted. Treatment-related side effects were uncommon (reported in 2.2 to 8.7% of patients) and considered mild. These included water retention in the flopropione group and nausea, diarrhea, constipation, and itchy skin in the naftopidil group.

Authors concluded that naftopidil is a safe and effective treatment for distal ureteral stones measuring 10 mm or less. The stone expulsion rate and time until expulsion was better with naftopidil than with flopropione.