polyethylene glycol & electrolytes (Rx, OTC)

Frequency Not Defined

Abdominal bloating

Abdominal cramping

Abdominal distention

Colonic mucosal aphthous ulcerations

Diarrhea

Flatulence

Ischemic colitis

Nausea

Postmarketing Reports

Cardiovascular: Arrhythmia, atrial fibrillation, peripheral edema, asystole, and acute pulmonary edema after aspiration

Nervous system: Tremor, seizure

Hypersensitivity: Urticaria/rash, pruritus, dermatitis, rhinorrhea, dyspnea, chest and throat tightness, fever, angioedema, anaphylaxis and anaphylactic shock

Gastrointestinal: Nausea, abdominal fullness and bloating are the most common adverse reactions (occurred in up to 50% of patients); less common adverse reactions include: abdominal cramps, vomiting, “butterfly-like” infiltrates on chest X-ray after vomiting and aspirating PEG, anal irritation, and upper GI bleeding from Mallory-Weiss Tear, esophageal perforation [usually with gastroesophageal reflux disease (GERD)

Contraindications

Hypersensitivity; ileus gastrointestinal obstruction, gastric retention, toxic colitis, bowel perforation, toxic megacolon

Cautions

Osmotic laxative products may produce colonic mucosal aphthous ulcerations, including reports of more serious cases of ischemic colitis necessitating hospitalization

Concomitant use of stimulant laxatives may increase risk of ischemic colitis; not recommended; consider potential for mucosal aphthous ulceration as a result of bowel preparation, especially when evaluating colonoscopy results in patients with known or suspected inflammatory bowel disease

Generalized tonic-clonic seizures and/or loss of consciousness reported in patients with no prior history of seizures, which resolved with correction of fluid and electrolyte abnormalities; use caution in patients with history of seizures or who are at increased risk of seizures, including concomitant administration of medications that lower seizures threshold, patients withdrawing from alcohol or benzodiazepines, and patients with unknown or suspected hyponatremia or low serum osmolality

Use with caution and observe unconscious or semiconscious patients with impaired gag reflex or other swallowing abnormalities or those who are otherwise prone to regurgitation or aspiration during administration; observe these patients during administration, especially if it is administered via nasogastric tube

Avoid use in patients with bowel obstruction, megacolon, perforated bowel, ulcerative colitis, toxic colitis, gastric retention

Not indicated for children <2 years because of risk of hypoglycemia, dehydration, and hypokalemia

When using PEG as laxative, do not give for >1 week

Electrolyte imbalance reported with prolonged use

Risk of fluid and electrolyte abnormalities; electrolyte abnormalities can lead to arrhythmias, seizures, and renal impairment; patients should maintain adequate hydration before, during, and after treatment; consider post colonoscopy lab test if patient becomes dehydrated or experiences significant vomiting after treatment

May cause arrhythmia; use caution with patients at risk of cardiac arrhythmia, including unstable angina, congestive heart failure, recent MI, uncontrolled arrhythmias, or cardiomyopathy; may consider pre- and post- dose ECG in patients at risk

Do not combine product with starch-based thickeners; polyethylene glycol (PEG), a component of the mixture, when mixed with starch-thickened liquids, reduces viscosity of the starch-thickened liquid; when a PEG-based product used for another indication was mixed in starch-based pre-thickened liquids used in patients with dysphagia, thinning of the liquid and cases of choking and potential aspiration were reported

Use caution in patients with renal impairment and/or in patients taking medications that may adversely affect renal function, including ACE inhibitors, NSAIDs, diuretics, and ARBs; instruct patients with renal impairment to remain adequately hydrated; may consider pre- and post-dose lab tests (electrolytes, creatinine, BUN) in these patients ; ensure adequate hydration, and consider laboratory testing

Directly observe administration to patients at risk for aspiration

Products are not for direct ingestion but require dilution with water

Use caution in patients >60 years; serious adverse events reported

Pregnancy category: C

Lactation: No data available

Pregnancy Categories

A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA: Information not available.

Mechanism of Action

Osmotic laxative; causes water retention in stool, causing increase in stool frequency

Absorption

Not absorbed

Bioavailability: 0.2%

Onset: 24-96 hr

Elimination

Excretion: Feces (93%), urine (0.2%)

Oral Administration

Product instructions vary for bowel prep; refer to instructions in package or provided by physician

Refrigerate before administering to improve palatability

Have patient fast at least 3-4 hr before administering PEG

Encourage rapid drinking of each portion

MiraLax: Bottle top is measuring cup marked to contain 17 g

Instruct patients to hydrate adequately with water and/or clear liquids before, during, and after use