Typical Restoralax Dose for Adults
The standard dose of Restoralax (polyethylene glycol 3350) for adults is 17 grams once daily, mixed in 8 ounces (approximately 250 mL) of liquid. 1
Dosing Details
The 2023 AGA-ACG clinical practice guideline establishes this as the FDA-approved dose for treating occasional constipation, based on high-quality evidence from randomized controlled trials 1. This dosing regimen:
- 17 grams = 1 capful (using the manufacturer's measuring cap)
- Mixed in 8 ounces of any beverage
- Taken once daily
- Can be used safely for up to 6 months based on clinical trial data 1
Alternative Dosing Considerations
While 17 grams once daily is standard, the evidence shows some variation:
- For chronic constipation: Some European studies used 17.5 grams of PEG with electrolytes twice daily (total 35 grams/day), though this formulation differs from standard Restoralax 1
- For rapid relief: A single 68-gram dose has been studied for relief within 24 hours, though this is not standard practice 2
- Dose titration: While not FDA-approved, some studies allowed titration up to 41.1 grams/day based on response 3
Practical Measurement
If patients lack the manufacturer's cap, household measuring devices can approximate doses 4:
- 1 leveled tablespoon ≈ 10 grams
- 1 leveled teaspoon ≈ 3.3 grams
- Therefore, approximately 1.5-2 leveled tablespoons ≈ 17 grams
However, using the manufacturer's cap or a kitchen scale provides the most accurate measurement.
Duration and Efficacy
- Response is typically seen within the first week, with optimal efficacy by week 2 1
- Efficacy is sustained and durable over 6 months of continuous use 1
- Can be used after a trial of fiber supplementation or in combination with fiber 1
Common Side Effects
Patients should be counseled about expected effects 1:
- Abdominal distension
- Loose stools (dose-dependent)
- Flatulence
- Mild nausea
- Most gastrointestinal adverse events decrease markedly after the first week 5
Important Caveat
The 17-gram once-daily dose is FDA-approved specifically for "occasional constipation," not chronic idiopathic constipation (CIC). However, the guideline panel strongly recommends its use for CIC based on moderate-quality evidence showing significant improvements in bowel movements, symptom relief, and quality of life 1.