What is the maximum dose of Miralax (Polyethylene Glycol 3350)?

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From the Research

The maximum recommended dose of MiraLAX (polyethylene glycol 3350) for adults is 17 grams (one capful or one heaping tablespoon) once daily, which should not be exceeded without medical supervision. This dose can be mixed in 4-8 ounces of any beverage and should be taken for no longer than 7 days without consulting a healthcare provider 1. For children, dosing should be determined by a pediatrician as there are different recommendations based on age and weight. MiraLAX works by drawing water into the colon to soften stool and increase bowel movements, typically producing results within 1-3 days.

Taking more than the recommended dose can lead to excessive fluid loss, electrolyte imbalances, and severe diarrhea. If constipation persists after 7 days of use, it's essential to seek medical advice as this could indicate a more serious underlying condition requiring different treatment. The efficacy and safety of polyethylene glycol-based preparations have been supported by good evidence, suggesting their use as first-line laxatives 2, 1.

Some key points to consider when using MiraLAX include:

  • The importance of not exceeding the recommended dose without medical supervision
  • The need for pediatricians to determine dosing for children based on age and weight
  • The potential for excessive fluid loss, electrolyte imbalances, and severe diarrhea with higher-than-recommended doses
  • The importance of seeking medical advice if constipation persists after 7 days of use.

It's also worth noting that polyethylene glycol-based preparations, like MiraLAX, have been shown to be safe and effective in various populations, including geriatrics 3, and are often recommended as a first-line treatment for constipation.

References

Research

Evidence-based treatment recommendations for OTC management of chronic constipation.

Journal of the American Association of Nurse Practitioners, 2022

Research

Review of efficacy and safety of laxatives use in geriatrics.

World journal of gastrointestinal pharmacology and therapeutics, 2016

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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