The rationale behind whole-bowel irrigation (WBI) is to prevent absorption of ingested matters (eg, extended-release medications, drug packets) by inducing a liquid stool through use of a osmotically balanced polyethylene glycol electrolyte solution (PEG-ES; eg, Go-LYTELY). [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 more than 12 hours after the overdose) had reduced peak serum lithium concentrations, fewer intensive care unit admissions, and a lower Poisoning Severity Score.  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. 
In 2004, the American Academy of Clinical Toxicology and the European Association of Poisons Centres and Clinical Toxicologists updated a position statement on WBI and other GI decontamination methods.  This position statement, based on literature reviews and expert agreement, serves 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 is not recommended as a routine GI decontamination method for the poisoned patient. It should, however, be considered in certain situations (see Indications and Contraindications). 
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 Treatment, Complications). 
WBI may be considered in the following circumstances:
Contraindications for WBI include the following:
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,  fluoxetine,  theophylline,  cocaine,  and sustained-release preparations of carbamazepine  revealed that WBI decreases the efficacy of AC by increasing the rate of desorption of xenobiotics already attached to the AC when the two therapies are used simultaneously or when WBI is used shortly after AC.
Conversely, some studies demonstrated increased binding capacity of mexiletine and imipramine to charcoal when PEG-ES was added. [22, 23] SDAC administered with PEG-ES was also shown to significantly decrease the likelihood of seizures from venlafaxine overdose in comparison with WBI treatment alone.  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.