Can Miralax (polyethylene glycol) be taken twice daily?

Miralax (Polyethylene Glycol) Can Be Taken Twice Daily

Yes, Miralax (polyethylene glycol) can be taken twice daily in certain situations, though the standard dosing is once daily. 1

Standard Dosing Information

The FDA-approved standard dosing for Miralax (polyethylene glycol 3350) is:

• Adults and children 17 years and older: One 17g dose (one capful or packet) once daily
• Mix with 4-8 ounces of beverage (cold, hot, or room temperature)
• Ensure powder is fully dissolved before drinking
• Standard duration: Do not use for more than 7 days without medical supervision 1

When Twice Daily Dosing May Be Appropriate

In certain clinical situations, twice daily dosing of polyethylene glycol may be considered:

1. Severe constipation: For patients with more severe constipation who don't respond adequately to once-daily dosing

2. Specific medical conditions: For patients with certain gastrointestinal conditions that require more aggressive treatment

3. Cardiac amyloidosis patients: The American College of Cardiology specifically mentions polyethylene glycol as a treatment option for constipation in these patients, which can be used multiple times daily as needed 2

Safety Considerations for Twice Daily Dosing

Research supports the safety of polyethylene glycol for extended use:

• A 12-month study of polyethylene glycol at the standard 17g daily dose showed it was safe and effective for long-term treatment of chronic constipation with no evidence of tachyphylaxis (diminished response over time) 3

• No clinically significant changes in electrolytes or other laboratory values were observed even with extended use 3

• Even higher doses (up to 68g in a single dose) have been studied for rapid relief of constipation without significant adverse effects 4

Potential Side Effects

Common side effects that may occur, especially with higher doses:

• Diarrhea
• Loose stools
• Flatulence
• Nausea
• Abdominal discomfort

These effects are generally mild to moderate in severity 3

Important Precautions

1. Consult a healthcare provider: Before increasing to twice daily dosing, patients should consult their healthcare provider

2. Adequate hydration: Ensure sufficient fluid intake when taking polyethylene glycol, especially at higher doses

3. Monitor for electrolyte imbalances: While uncommon, patients on twice daily dosing should be aware of symptoms of electrolyte disturbances

4. Duration of use: The FDA label states not to use for more than 7 days without medical supervision 1

Recommendations for Different Patient Groups

• Elderly patients: Polyethylene glycol has been shown to be safe and effective in elderly patients, including those in institutional settings 5

• Patients with renal impairment: Polyethylene glycol is generally safe as it is minimally absorbed systemically

• Patients with hepatic impairment: No dose adjustment is typically necessary

Conclusion

While the standard FDA-approved dosing for Miralax is 17g once daily, twice daily dosing can be used in specific situations under healthcare provider supervision. Research supports the safety of polyethylene glycol even at higher doses and for extended periods. Always consult with a healthcare provider before changing the recommended dosing regimen.