What is the recommended dosing frequency for Mucinex (Guaifenesin) ER 600 mg?

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Mucinex ER 600 mg Dosing Frequency

Mucinex ER (extended-release guaifenesin) 600 mg should be given every 12 hours, with a maximum of 2 doses (1200 mg total) in 24 hours. 1

Standard Dosing Regimen

  • Adults and children ≥12 years: Take 1-2 tablets (600-1200 mg) every 12 hours 1, 2
  • Maximum daily dose: Do not exceed 2400 mg (4 tablets) in 24 hours 1
  • The extended-release formulation was specifically developed to reduce dosing frequency from every 4 hours (required for immediate-release guaifenesin) to every 12 hours while maintaining therapeutic efficacy 2

Key Pharmacokinetic Considerations

  • Bioequivalence: The 1200 mg ER formulation given every 12 hours provides steady-state exposures equivalent to 400 mg immediate-release guaifenesin given every 4 hours 2
  • Food effects: Food may delay absorption (later Tmax) but does not affect overall drug exposure (AUC), so the medication can be taken with or without food 2
  • The bi-layer tablet design allows for both immediate and extended release, maintaining therapeutic levels throughout the 12-hour dosing interval 2

Clinical Application

  • The 12-hour dosing schedule offers significant convenience and improved adherence compared to the 4-hour dosing required for immediate-release formulations 2, 3
  • Multiple daily doses are unnecessary with the ER formulation, as it maintains 24-hour therapeutic effect with twice-daily administration 3
  • The safety profile is well-established, with predominantly mild gastrointestinal and nervous system adverse events when used at recommended doses 4

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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