Whole-Bowel Irrigation

Updated: Jun 15, 2022
  • Author: Rittirak Othong, MD, FACMT, FTCEP; Chief Editor: Vikram Kate, MBBS, MS, PhD, FACS, FACG, FRCS, FRCS(Edin), FRCS(Glasg), FFST(Ed), FIMSA, MAMS, MASCRS  more...
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The rationale behind whole-bowel irrigation (WBI) is to prevent absorption of ingested matter (eg, extended-release medications or drug packets) by inducing a liquid stool through use of a osmotically balanced polyethylene glycol electrolyte solution (PEG-ES). [1, 2]

A study of acute-on-chronic lithium toxicity concluded that patients who received WBI within 12 hours of an acute overdose (compared with those receiving WBI >12 hours after the overdose) had reduced peak serum lithium concentrations, fewer intensive care unit (ICU) admissions, and a lower Poisoning Severity Score. [3] Early WBI as a means of gastrointestinal (GI) decontamination may lessen the need for more invasive treatment, such as hemodialysis in sustained-release lithium or potassium chloride overdose. [3, 4]

Administration of PEG-ES generally requires use of a nasogastric (NG) tube because of the large volume (>1 L in an average adult) that must be ingested over a short period. However, if insertion of an NG tube is difficult, an awake and alert patient may drink the solution instead.

WBI can also be used safely in pediatric patients, as revealed by a study of 176 patients ranging in age from 4 months to 12 years. Only minor adverse events (eg, abdominal bloating or vomiting) occurred, and no deaths were reported. [5]

In 2004, the American Academy of Clinical Toxicology (AACT) and the European Association of Poisons Centres and Clinical Toxicologists (EAPCCT) updated a position statement on WBI and other GI decontamination methods. [2] This statement, based on literature reviews and expert agreement, served as a guideline for the management of in-hospital poisoned patients. Because of the lack of controlled clinical trials showing that WBI improves clinical outcome, WBI was not recommended as a routine GI decontamination method for the poisoned patient. It should, however, be considered in certain situations (see Indications and Contraindications). [6]

PEG-ES may enhance tablet dissolution of non-sustained-release preparations. An in-vitro model study comparing dissolution rates of non-sustained-release acetaminophen demonstrated increased dissolution by PEG-ES in comparison with normal saline. [7]

In 2015, the AACT and EAPCCT conducted a systematic review on articles published from 2003 through 2013, using multiple databases to look for new data on WBI. They found no new evidence with sound methodology to change the 2004 recommendations; however, they did find more evidence on complications from WBI (see Technique, Complications). [8]

In 2022, a multicenter retrospective observational study revealed that when WBI was done according to indications advised by poison centers, poisoned patients treated with WBI experienced significantly less clinical decompensation than patients not treated with WBI (11% vs 32%), despite  having similar baseline characteristics before WBI was initiated. [9] In multivariate analysis, intensive care unit (ICU) admission and not performing WBI were the two factors predictive of clinical deterioration. 



WBI may be considered in the following circumstances:

  • Prior to surgery, colonoscopy, or a barium enema to cleanse the bowel
  • Ingestion of a significant or life-threatening amount of sustained-release medications, [1, 2, 10, 11, 12] such as sustained-release potassium chloride [4]
  • Ingestion of a significant or life-threatening amount of medications or xenobiotics that are not adsorbed by activated charcoal (AC), [11] or a situation where no other GI decontamination methods are appropriate [1, 2] (eg, iron supplements, lead foreign body, [13]  or lithium [3] )
  • Ingestion of illicit drug packets [1, 2]
  • Ingestion of whole transdermal patches (eg, transdermal fentanyl patch or transdermal clonidine patch) [14, 15, 16]
  • Ingestion of multiple water beads with no signs of bowel obstruction [17]
  • Overdose with pharmacobezoar formation detected on abdominal radiography [9]
  • Before surgery, colonoscopy, or a barium enema to cleanse the bowel


Contraindications for WBI include the following:

  • Unprotected airway or compromised airway [1, 2]
  • Clinically significant GI bleeding [1, 2]
  • Intractable vomiting [1, 2]
  • Unstable vital signs [1, 2, 19]
  • Signs of leakage of illicit drug packets (eg, tachycardia, hypertension, hyperthermia in a patient who has ingested cocaine packets); a surgical consult should be obtained in this circumstance [1, 20]

Either WBI or single-dose AC (SDAC) is used for GI decontamination. Sometimes, WBI is used in conjunction with SDAC to enhance GI decontamination.

Many studies done with chlorpromazine, [21] fluoxetine, [22] theophylline, [23] cocaine, [24] and sustained-release preparations of carbamazepine [25] revealed that WBI decreased the efficacy of AC by increasing the rate of desorption of xenobiotics already attached to the AC when the two therapies were used simultaneously or when WBI was used shortly after AC.

Conversely, some studies demonstrated increased binding capacity of mexiletine and imipramine to charcoal when PEG-ES was added. [26, 27] SDAC administered with PEG-ES was also shown to significantly decrease the likelihood of seizures from venlafaxine overdose in comparison with WBI treatment alone. [28] WBI is not needed in cases where AC is known to adsorb the xenobiotic effectively; however, it may be considered as an adjunct measure in certain overdose situations. [8]