A parallel, randomized, double-blind, placebo-controlled study to investigate the effect of SagaPro on nocturia in men. OBJECTIVE: This study aimed to investigate the effect of SagaPro, a product derived from Angelica archangelica leaf, on nocturia. MATERIAL AND METHODS: Sixty-nine male patients 45 years or older with at least two nocturnal voids were randomized to receive SagaPro or placebo in a double-blind design for 8 weeks. Voiding diaries were assessed before and after the treatment. RESULTS: The results indicate that SagaPro is safe. The actual number of nocturnal voids (ANV), nocturnal polyuria index (NPi) and nocturnal bladder capacity index (NBC index) decreased in the test population, but there was no significant difference between the treatment groups. Subsequent subgroup analysis showed that SagaPro significantly reduced the NBC index and nocturnal voids per sleeping hour in comparison to the placebo in participants with baseline NBC index above 1.3. When participants with sleep disorders were excluded from this group, ANV was also significantly reduced for the SagaPro group in comparison to the placebo group. CONCLUSION: SagaPro, made from an extract of the medicinal herb Angelica archangelica, is safe. This study did not show that SagaPro improved nocturia overall compared to placebo. Subgroup analysis suggested a beneficial effect in individuals with decreased nocturnal bladder capacity, which warrants further study.