Intraprostatic botulinum neurotoxin type a injection for benign prostatic hyperplasia: Preliminary results with a newly purified neurotoxin

Teruhiko Yokoyama, Yumiko Yamamoto, Tomonori Suzuki, Keiji Oguma, Atsushi Nagaia

Research output: Contribution to journalArticle

7 Citations (Scopus)


Several studies have demonstrated the efficacy of intraprostatic injection of botulinum neurotoxin type A (BoNT/A) against symptomatic benign prostatic hyperplasia (BPH). The most commonly used BoNT/A product, Botox®, forms large complexes and composed of neurotoxin (NTX) as well as non-toxic components. We purified NTX lacking non-toxic components. We investigated the efficacy of this newly purified NTX for men with BPH. Ten male patients (mean age, 70.0 years) with BPH received 100 units (prostate volume [PV] <30ml) or 200 units (PV > 30ml) of NTX injected into the prostate via a minimally invasive outpatient technique. Evaluation included uroflowmetry, postvoid residual urine volume (PVR), PV, and International Prostate Symptom Score (IPSS) measured at baseline and 1, 3, 6, and 12 months post-treatment. The status of 7 of the 10 patients examined was found to have improved within 1 month of treatment. The mean IPSS decreased from 23.8 ± 7.0 to 16.3 ± 10.3 (p - 0.0093) at 1 month, to 14.9 ± 8.2 (p = 0.0074) at 3 months, and to 16.9 ± 7.3 (p = 0.018) at 12 months. The mean PV decreased from 47.8 ± 21.2 to 39.2 ± 19.5 ml (p = 0.0076) at 3 months. The PVR improved at 3 and 6 months post-treatment Intraprostatic NTX injection induces prostate shrinkage and is effective in men with BPH.

Original languageEnglish
Pages (from-to)291-297
Number of pages7
JournalActa Medica Okayama
Issue number4
Publication statusPublished - 2012



  • Benign prostatic hyperplasia
  • Botulinum neurotoxin type A
  • Therapy

ASJC Scopus subject areas

  • Medicine(all)
  • Biochemistry, Genetics and Molecular Biology(all)

Cite this