Standard Miralax Dose for Adults
The standard dose of Miralax (polyethylene glycol 3350) for adults is 17 grams (one packet or one heaping tablespoon) dissolved in 8 ounces of any beverage once daily. 1, 2
Dosing Details
- Standard starting dose: 17 grams once daily mixed in 8 oz of liquid (cold, hot, or room temperature) 3, 1, 2
- Maximum dose for chronic constipation: Some patients may require 17 grams twice daily (34 grams total per day) for optimal symptom control 4, 1
- Duration: FDA-approved for up to 7 days of over-the-counter use, though clinical guidelines support longer-term use under medical supervision 2, 3
Administration Instructions
- Ensure the powder is fully dissolved before drinking; do not consume if clumps remain 2
- Can be mixed with any beverage at any temperature 2
- Do not combine with starch-based thickeners used for swallowing difficulties 2
- Take with or without meals, though taking with meals may improve gastrointestinal tolerability 3
Dose Titration
- If inadequate response after 1-2 weeks: Increase to 17 grams twice daily 1, 3
- Greatest efficacy: Typically occurs in week 2 of treatment 1, 5
- Response is durable: Demonstrated effectiveness over 6-12 months of continuous use 1, 3
Common Pitfalls to Avoid
- Do not exceed 7 days without medical supervision when using over-the-counter formulations 2
- Ensure adequate fluid intake throughout the day to prevent dehydration and optimize effectiveness 3, 1
- Common side effects include bloating, abdominal distension, flatulence, and loose stools—these can often be managed by dose adjustment 3, 1
- Do not use fiber supplements concurrently for medication-induced constipation, as they may worsen symptoms 4