Reduction in Bowel Program Duration With Polyethylene Glycol Based Bisacodyl Suppositories; Steven J. Stiens. MD

ABSTRACT. Stiens SA. Reduction in bowel program duration with polyethylene glycol based bisacodyl suppositories. Arch Phys Med Rehabil 1995;76:674-7.

The neurogenic bowel caused by spinal cord injury frequently requires a bowel program (BP) with stimulant suppositories for effective defecation. Objective: The effectiveness of bowel programs initiated by hydrogenated vegetable oil based bisacodyl (HVB) suppositories was compared with that of polyethylene glycol based bisacodyl suppositories (PGB). Design: Single subject, randomized treatment. Setting: Outpatient. Subject: Chronic T2 complete spinal cord injury (SCI) Intervention: The suppository for the every third-day BP was randomized to PGB or HVB. The times in minutes of the following BP events were recorded: suppository insertion, first flatus begin stool flow, end stool flow, and transfer off toilet. Outcome Measures: BP event times were used to derive BP intervals: suppository insertion to first flatus Time to Flatus, first flatus until begin stool flow = Flatus to Stool Flow, begin stool flow until end stool flow Defecation Period, end stool flow until the transfer off the toilet Wait Until Transfer, and suppository insertion until transfer off the toilet = Total BP Time. The number of digital stimulations required and the amount of stool results were recorded. Results: The data included two groups of BPs: HVB (N=13) and PGB (N=13). Wilcoxon’s rank sum tests were used to compare mean times for each of the BP intervals: Time to Flatus (HVB 31 minutes, PGB 10 minutes, p <.0001), Flatus to Stool Flow (HVB 6.0 minutes, PGB 5.9 minutes, p =.9578), and the Defecation Period (HVB 31, PGB 21, p =.0043). The average BP Time was HVB = 85 minutes and PGB = 46 minutes showing a statistically (p <.0001) and clinically relevant difference. 1995 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Injuries to the spinal cord (SCI) that result in upper motor neuron damage frequently produce neurogenic bowel dysfunction. The upper motor neuron bowel is characterized by fecal retention and uniformly requires a scheduled evacuation plan to avoid impaction and incontinence. These bowel programs (BPs) remain time-consuming processes that may be detrimental to quality of life.¹ Bowel regimens may last longer than 3 hours and still produce insufficient results.² Consequently, despite tedious and exacting BP regimens, serious problems with bowel evacuation are still reported from as many as 20% of people with SCI.³  

Suppositories consisting of active laxative ingredients dispersed in a base substance are commonly used in a BP. Bisacodyl is the most commonly used active ingredient in rectal chemical stimulant preparations for defecation. This compound, a diphenylmethane derivative (bis (p-acetoxy phenyl)-2-pyridymethane) was first introduced for use as a laxative in 1953 because of its structural similarity to phenolphthalein. Acting as a contact laxative, bisacodyl is practically insoluble in water and sparingly soluble in alcohol. 

From the Veterans Affairs Medical Center SC! Service and Department of Rehabilitation. University of Washington, Seattle. Supported In pare by Research Enrichment Program for Physiatrists. NIDRR no. H133P10011  Submitted for publication September 2. 1994, Accepted in revised form February 6,1995. No commercial company having a direct financial interest in the results of the research supporting this article has or will confer a beneth upon the authors or upon any organizations with which the authors are associated.  Reprint requests to Steven A. Stiens. MD, University of Washington, Department of Rehabilitation. Mail Location RJ-30, Health Sciences Building 8B938. 1959 NE Pacific, Seattle, WA 98195. © 1995 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation 003-9993/95/76O7-322 $3.00/0

Administered rectally in a water suspension, bisacodyl acts within 3 minutes to produce suppression of rhythmic stationary spike wave activity and increases spasmodic propulsive peristaltic spike activity,⁴  

Bisacodyl is available in many rectal preparations including suppositories, enemas, mini-enemas, and solutions.5 Typically. 10-mg suppositories are used because of the ease of insertion and retention. The most common suppository preparation includes bisacodyl powder distributed within a hydrogenated vegetable oil base (HVB).⁵ Bisacodyl suppositories with a vegetable oil base often require a prolonged period to produce defecation and can cause continued mucosal irritation with resultant mucus accidents hours after the BP. Water-miscible suppositories have recently been used. Bisacodyl suppositories made with the polyethylene glycol polymer bases have been anecdotally reported to produce quicker elimination.⁶  

This study was performed to compare BP times using HVB and polyethylene glycol-based bisacodyl (PGB) suppositories. The primary question in clinical practice relates to the effectiveness of a new treatment regimen in a particular patient. The idiographic, single case study method is used here to show a method of monitoring patient progress with changes in response to a pharmacological bowel elimination regimen.⁷ 

METHOD 

The subject is a 35-year-old white man with a 10-year history of T2 complete stable paraplegia that resulted from a spinal cord arteriovenous malformation. Physical examina- tion showed moderate scoliosis and decreased abdominal