MiraLax

Artificial Tears and Ocular Lubricants
Osmotically-Acting Laxatives

For storage information, see specific product information within the How Supplied section.

Polyethylene glycol 3350 powder for oral solution can be administered at any time of day; however, administration in the morning is suggested. Use should not exceed 7 days.
Can be taken orally on a full or empty stomach.
Measure dosage with the calibrated cap provided with the bulk product, or, open the 17-gram packet (if packet dosing is appropriate).
Mix dose well in a full glass (120 to 240 mL or 4 to 8 ounces) of water, juice, soda, coffee, or tea prior to administration. Ensure that the powder is fully dissolved; the patient should not drink if there are any clumps.
Do NOT combine with starch-based thickeners.
Have patient drink entire prepared dose after it has been dissolved in the proper liquid.
 
Polyethylene glycol 3350 powder for oral solution plus carbohydrate-electrolyte drink (e.g., Miralax + Gatorade) for bowel preparation†
NOTE: The use of polyethylene glycol 3350 powder for oral solution for bowel preparation is not approved by the FDA.
Several regimens have been described. One possible split-dose regimen begins by dissolving 238 grams PEG 3350 (e.g., Miralax) in 64 ounces of a lightly colored carbohydrate-electrolyte drink (e.g., Gatorade); may be chilled.
Day before exam: Patient drinks 32 ounces of solution at a rate of 16 ounces/h starting at 4 PM the day before the colonoscopy; alternatively, the patient may pretreat with two 5 mg bisacodyl tablets with clear liquids at 12 PM.
Morning of exam: Patient drinks the remaining 32 ounces of solution at a rate of 16 ounces/hour, approximately 5 hours before the scheduled start time of the colonoscopy.
Guidelines recommend split-dose over single-dose bowel preparation as a key measure for improving the quality and cost-effectiveness of colonoscopies as a screening test.

anaphylactoid reactions / Rapid / 0-1.0

fecal incontinence / Early / 0-1.0

flatulence / Early / 1.0-10.0
diarrhea / Early / 1.0-10.0
nausea / Early / 1.0-10.0
rhinorrhea / Early / 0-1.0
pruritus / Rapid / 0-1.0
urticaria / Rapid / 0-1.0
fecal urgency / Early / Incidence not known
abdominal pain / Early / Incidence not known

GaviLax, GIALAX, GlycoLax, Healthylax, MiraLax, Smooth LAX, Visine Dry Eye Relief, Vita Health

OTC, Rx

Osmotic laxative that does not contain electrolytes; no systemic absorption; draws water into the stool to ease bowel movements
Used to treat constipation in adult and pediatric patients
Consistently improves constipation even with long-term use; exhibits side effect profile similar to placebo

17 g PO once daily as needed. In clinical trials, a dose of 34 g/day PO was also evaluated; however, the frequency of adverse effects, such as diarrhea, was greater in persons receiving the higher dose.

17 g PO once daily as needed. In clinical trials, a dose of 34 g/day PO was also evaluated; however, the frequency of adverse effects, such as diarrhea, was greater in persons receiving the higher dose.

0.4 g/kg/day PO initially; a dose range of 0.2 to 1.8 g/kg/day PO have been reported. Max: 17 g/day. In a randomized controlled trial, the authors noted efficacy, but did report an increase in GI-related adverse events with doses 0.8 g/kg/day or more. In an observational study (n = 83, including 39 with encopresis), a mean dose of 0.75 g/kg/day (range, 0.2 to 1.8 g/kg/day) PO was used for a mean of 8.7 months; the most common side effect (10%) was frequent loose stools, which responded to dosage reduction.

0.4 g/kg/day PO initially; a dose range of 0.2 to 1.5 g/kg/day PO has been reported. In a trial of infants and toddlers, the mean effective dose was 0.8 to 1.1 g/kg/day.

0.25 grams/kg, 0.5 grams/kg, 1 gram/kg, or 1.5 grams/kg PO (not exceeding 100 grams/day PO) and administered in 1 to 4 divided doses for 3 days, were effective in one trial. Impactions resolved in 75% of children overall. The doses of 1 gram/kg/day and 1.5 grams/kg/day were significantly more effective in resolving impactions. All dosages improved stool frequency and were well tolerated.

This is a second-line treatment regimen per guidelines, not usually recommended. 238 grams PEG 3350 (e.g., Miralax), dissolved in 64 ounces of carbohydrate-electrolyte drink (e.g., Gatorade) PO as a single or split-dose regimen with or without an adjunct laxative (10- to 20-mg bisacodyl tablets). While efficacy of bowel cleansing may be statistically less with this approach, it may have little clinical impact as polyp detection rates remained the same. Concerns regarding this regimen include the risk for electrolyte imbalance, specifically hyponatremia caused by diarrhea-induced volume depletion in the absence of a balanced electrolyte solution replacement. Reserve use for patients who cannot tolerate other bowel preparation regimens and whose risk of complications from electrolyte imbalance is low. Guidelines recommend split-dose over single-dose bowel preparation as a key measure for improving the quality and cost effectiveness of colonoscopies as a screening test.

17 g PO once daily as needed. PEG 3350 can be a useful adjunct for IBS-C to help improve stool frequency and consistency as needed; per guidelines, medications that target global IBS-C symptoms (e.g., guanylate cyclase-C agonists, lubiprostone) are preferred therapies.

†Indicates off-label use

Specific guidelines for dosage adjustments in hepatic impairment are not available; it appears that no dosage adjustments are needed.

Specific guidelines for dosage adjustments in renal impairment are not available; patients with renal disease or impairment should only use polyethylene glycol 3350 under supervision and advice of their doctor.

Acetaminophen; Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Atropine; Difenoxin: (Moderate) Diphenoxylate can decrease GI motility. Drugs used to treat constipation, such as laxatives, would counteract the effect of antidiarrheals. In general, it would be illogical to concurrently administer these drugs at the same time. If an antidiarrheal medication is needed, it would be wise to temporarily discontinue use of agents with laxative effects.
Bisacodyl: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Bumetanide: (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.
Calcium Phosphate, Supersaturated: (Moderate) Sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous should not be combined with additional laxatives or purgatives when being used to evacuate the bowel prior to colonic radiologic examinations or surgery. Use in patients using small doses of polyethylene glycol 3350 (e.g., Miralax) may be permissable, as long as the patient does not use their chronic laxative therapy on the day of the preparation. Watch for electrolyte and fluid abnormalities in all patients using bowel preparations.
Castor Oil: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Chlorpheniramine; Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Dichlorphenamide: (Moderate) Use dichlorphenamide and polyethylene glycol; electrolytes together with caution. Dichlorphenamide increases potassium excretion and can cause hypokalemia and should be used cautiously with other drugs that may cause hypokalemia including laxatives. Measure potassium concentrations at baseline and periodically during dichlorphenamide treatment. If hypokalemia occurs or persists, consider reducing the dichlorphenamide dose or discontinuing dichlorphenamide therapy.
Diphenoxylate; Atropine: (Moderate) Diphenoxylate can decrease GI motility. Drugs used to treat constipation, such as laxatives, would counteract the effect of antidiarrheals. In general, it would be illogical to concurrently administer these drugs at the same time. If an antidiarrheal medication is needed, it would be wise to temporarily discontinue use of agents with laxative effects.
Docusate Sodium; Senna: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Ethacrynic Acid: (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.
Furosemide: (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.
Guaifenesin; Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Homatropine; Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Hydrocodone: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Hydrocodone; Ibuprofen: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Hydrocodone; Pseudoephedrine: (Minor) Concurrent use of hydrocodone with strong laxatives that rapidly increase gastrointestinal motility, such as polyethylene glycol, may decrease hydrocodone absorption. Closely monitor patients for changing analgesic requirements or adverse events.
Lactulose: (Major) In general, other laxatives, such as polyethylene glycol 3350, should not be used concurrently with lactulose, especially during the initial phase of therapy for portal-systemic encephalopathy, because the loose stools resulting from their use may falsely suggest that adequate lactulose dosage has been achieved.
Loop diuretics: (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.
Pimozide: (Moderate) According to the manufacturer of pimozide, the drug should not be coadministered with drugs known to cause electrolyte imbalances, such as polyethylene glycol used in colon-cleansing regimens, except when indicated. Use in patients using small doses of polyethylene glycol 3350 (e.g., Miralax) may be permissable, as long as not excessive. Pimozide is associated with a well-established risk of QT prolongation and torsade de pointes (TdP), and electrolyte imbalances (e.g., hypokalemia, hypocalcemia, hypomagnesemia) may increase the risk of life-threatening arrhythmias. Pimozide is contraindicated in patients with known hypokalemia or hypomagnesemia.
Polyethylene Glycol; Electrolytes; Bisacodyl: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Senna: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Sodium Phosphate Monobasic Monohydrate; Sodium Phosphate Dibasic Anhydrous: (Moderate) Sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous should not be combined with additional laxatives or purgatives when being used to evacuate the bowel prior to colonic radiologic examinations or surgery. Use in patients using small doses of polyethylene glycol 3350 (e.g., Miralax) may be permissable, as long as the patient does not use their chronic laxative therapy on the day of the preparation. Watch for electrolyte and fluid abnormalities in all patients using bowel preparations.
Stimulant Laxatives: (Moderate) When polyethylene glycol is used as pre-procedure bowel preparation, avoid concomitant use of stimulant laxatives. Colonic mucosal aphthous ulcerations and ischemic colitis have been observed following use of osmotic laxatives for bowel preparation and concomitant use of stimulant laxatives may increase this risk.
Torsemide: (Moderate) Monitor renal function and serum electrolytes and ensure adequate hydration before and after concomitant loop diuretic and polyethylene glycol 3350 use. Concomitant use may increase the risk for fluid and electrolyte abnormalities and renal injury.

GaviLax/GIALAX/GlycoLax/Healthylax/MiraLax/Polyethylene Glycol 3350/Smooth LAX/Vita Health Oral Pwd F/Recon: 17g
Visine Dry Eye Relief Ophthalmic Drops: 1%

34 grams/day PO for daily chronic use.

34 grams/day PO for daily chronic use.

17 years: 17 grams/day PO for constipation; up to 34 grams/day PO has been studied.
Less than 17 years: 0.8 grams/kg/day PO (Max: 17 grams/day PO) suggested for constipation. Up to 1.5 grams/kg/day PO (not to exceed 100 grams/day) for short term use for up to 3 days has been used for disimpaction.

2 years and older: 0.8 grams/kg/day PO (Max: 17 grams/day PO) suggested for constipation. Up to 1.5 grams/kg/day PO (not to exceed 100 grams/day) for short term use for up to 3 days has been used for disimpaction.
Less than 2 years: Up to 1.1 grams/kg/day PO has been suggested in some studies off-label for constipation.

Up to 1.1 grams/kg/day PO has been suggested in some studies off-label for constipation.

Safety and efficacy have not been established.

Polyethylene glycol 3350 is an osmotic agent which binds water and causes water to be retained within the stool. The lack of intestinal enzymatic degradation or bacterial metabolism of PEG 3350 contributes to the drug's effectiveness for idiopathic constipation; no tachyphylaxis was noted during clinical trials up to 24 months. In normal volunteers, low doses of PEG 3350 increased stool weight. In constipated patients, PEG 3350 softened stool consistency, increased stool frequency, and facilitated stool evacuation. PEG 3350 did not affect colonic transit time. Polyethylene glycol 3350 had no effect on the active absorption or secretion of glucose or electrolytes from the intestine.

Polyethylene glycol 3350 is administered orally as a solution in water.
Complete recovery of an administered dose occurred in the feces of normal volunteers. Roughly 0.2% of a dose has been absorbed systemically in some studies of PEG 3350; the systemically absorbed amount is quickly excreted in the urine. An attempt to study the recovery of PEG 3350 in constipated patients was not reliable, but results are expected to be similar to normal controls. PEG 3350 is not fermented within the GI tract by the colonic microflora; no metabolism occurs locally.

After oral administration of polyethylene glycol 3350, the dosage essentially remains within the GI tract.

Polyethylene glycol (PEG) 3350 is negligibly absorbed and metabolized in humans, making it unlikely to cause malformations. Animal studies do not indicate evidence of fetal harm. The American Gastroenterological Association recommends PEG 3350 as a first-choice laxative in pregnancy when non-pharmacologic methods (e.g., fluids, dietary fiber) are ineffective or inadequate for preventing or treating constipation. A stool softener such as docusate sodium is also considered low risk.

The safest laxatives for use in lactating women are those that are not systemically absorbed. Polyethylene glycol 3350 (PEG 3350) is a common food additive and is not significantly absorbed from the GI tract. Only 0.2% of an oral dose would be absorbed systemically by the lactating mother. It is not known if PEG 3350 is distributed into breast-milk, but significant passage seems unlikely. The American Gastroenterological Association states that PEG-3350 laxatives represent a low risk when used during breast-feeding.