Hirofumi Kurose, Hiroshi Kishimoto, Keisuke Komiya, Kosuke Ueda, Katsuaki Chikui, Keiichiro Uemura, Kiyoaki Nishihara, Makoto Nakiri, Shigetaka Suekane, Tsukasa Igawa
Background and Objectives: Given the limited therapeutic options for patients with persistent nocturia despite desmopressin treatment, we aimed to evaluate the short-term effects of add-on Gosha-jinki-gan therapy on hours of undisturbed sleep (HUS) and nocturia-related parameters in a real-world clinical setting. Materials and Methods: This retrospective study included 40 men aged ≥60 years with nocturnal polyuria who had ≥2 nocturnal voids or HUS ≤ 3 h despite desmopressin treatment. Add-on Gosha-jinki-gan (7.5 g/day) was initiated while concomitant medications were continued. Voiding diaries and validated questionnaires were assessed before treatment and at 1 and 4 weeks. Primary outcomes were the nocturnal voiding frequency, nocturnal urine volume, nocturnal polyuria index, and HUS. Secondary outcomes included the International Prostate Symptom Score (IPSS), Overactive Bladder Symptom Score (OABSS), Athens Insomnia Scale, and Patient Global Impression of Improvement (PGI-I). Results: The mean voided volume before desmopressin treatment was low (109.9 mL), suggesting reduced functional bladder capacity. Add-on Gosha-jinki-gan therapy was associated with a reduction in nocturnal voiding frequency (3.38 to 2.60 episodes/night, p < 0.0001) and nocturnal urine volume (p < 0.0001). The mean HUS increased from 116 to 186 min at 4 weeks (p < 0.0001), representing an extension of approximately 70 min and exceeding the clinically meaningful 3 h threshold. Sleep quality, assessed by the Athens Insomnia Scale, also improved significantly. No serious adverse events were observed. Conclusions: Add-on Gosha-jinki-gan therapy was associated with improvements in nocturia-related parameters and prolongation of HUS in patients with persistent nocturia despite desmopressin treatment. These findings should be considered preliminary and hypothesis-generating. Prospective controlled studies are required to determine whether add-on Gosha-jinki-gan provides benefits beyond desmopressin alone.