disorder clinic were reviewed. All participants underwent brain magnetic resonance imaging to augment diagnostic accuracy. For the same reason, metaiodobenzylguanidine (MIBG) cardiac scintigraphy was performed in most participants. Individuals with a history of abdominal surgery, gastrointestinal diseases such as ulcerative colitis and cholecystolithiasis, diabetes mellitus, and other systemic diseases that might potentially cause IPO or volvulus were excluded. For the same reason, individuals patients taking trihexyphenidyl and other anticholinergic agents were excluded.Two-hundred fifty individuals with PD (132 men, 118 women; mean age 67 (range 46-84); mean disease duration 5.3 years (range 1-15 years)) were enrolled in the study. Of these, six (2.4%) had been admitted to the gastroenterology unit because of emergency IPO (five cases) or sigmoid colon volvulus (case 3 and at the second admission of case 6) ( Table 1). All six patients had acute onset of abdominal bloating, pain, nausea, or vomiting. 1 Abdominal X-ray and computed tomography showed dilation of the colon with or without the small intestine in all six individuals. 1 Two cases with volvulus showed a double loop sign at the sigmoid colon, 1,4,5 which required emergency endoscopic reposition. The clinical features of the six individuals were as follows: mean age 78.5 (range 69-82); three male, three female; ordinary Hoehn Yahr motor grade 3.2 (range 2-5); illness duration 5.3 years (range 2-9 years; taking a large levodopa dose 420 mg/d (in 5); constipation; regular bowel medication (e.g., magnesium oxide) (in 5); urinary dysfunction (in 5); mean hospital stay 44 days (range 1-112 days); no recurrence after discharge for mean 1.3 years (range 1-4 years). One patient (case 2) died from aspiration pneumonia.Mechanisms of constipation in PD are prolonged colonic transit (autonomic) and disturbed defecation (somatic and autonomic), 1 reflecting Lewy body pathology in the myenteric plexus. 1 The incidence of IPO and volvulus in our cases (2.4%, 6/250) is almost in accordance with that found in the previous study (7.1%, 8/ 112). 2 After hospitalization, patients were started on mosapride (selective 5HT-4 stimulating agent), 6 domperidone (peripheral dopaminergic blocker), and Dai-Kenchu-Tou (an herbal medicine containing hydroxy-beta-sanshool with 5HT-3-stimulating properties), 7 which seemed to prevent the recurrence of IPO. In conclusion, the incidence of emergency IPO in individuals with PD at a movement disorder and gastroenterology clinics was 2.4%; all were older adults. Although rare, emergency IPO requires hospitalization and may have a poor outcome. Therefore, preventative treatment of constipation with prokinetic drugs is necessary particularly in older adults with PD.The present study was approved by the ethics committee at