MiraLAX · Toddlers
MiraLAX dose for a 2-year-old
There’s no single MiraLAX dose for all 2-year-olds, because pediatric guidelines dose it by weight: 0.2 to 0.8 g per kg per day. Most healthy 2-year-olds weigh about 9.5 to 15 kg (21 to 32 lb), so a daily dose usually falls between about 2 and 12 g, less than a full 17 g capful. Your child’s doctor should set the starting dose, since the package is labeled for ages 17 and up.
MiraLAX range for 2-year-olds by weight
| Weight at 24 months | Guideline range0.2-0.8 g/kg/day | Common start0.4 g/kg/day |
|---|---|---|
| Smaller 2-year-old (5th percentile)9.4 kg · 20.8 lb | 1.9-7.5 g | 3.8 gabout 22% of a capful |
| Typical 2-year-old (median)11.8 kg · 26 lb | 2.4-9.5 g | 4.7 gabout 28% of a capful |
| Larger 2-year-old (95th percentile)14.7 kg · 32.3 lb | 2.9-11.7 g | 5.9 gabout 35% of a capful |
Weights: World Health Organization. Dose range: ESPGHAN and NASPGHAN.
MiraLAX dose calculator
Getting a toddler to take it
- Stir it into 4 to 8 oz of water, milk or juice. It has no taste once dissolved.
- Split the day’s dose between two drinks if your toddler won’t finish one cup, as long as your doctor agrees.
- Give it at the same time each day and keep a simple poop diary for the doctor.
When to call the doctor
- Belly pain, vomiting, a swollen belly, or blood in the stool.
- Watery diarrhea after starting MiraLAX.
- No improvement after 1 to 2 weeks.
Common questions
How much MiraLAX can I give my 2-year-old?
Ask your child’s doctor for the dose. For a typical 2-year-old of about 12 kg (26 lb), the guideline range works out to about 2.4 to 9.6 g a day, and a common starting point (0.4 g/kg) is about 5 g, roughly a quarter of a capful.
How do I measure a quarter capful?
The cap’s fill line marks 17 g. For small doses, a kitchen scale that reads grams is more accurate than guessing a fraction of the cap.
How long until MiraLAX works in a toddler?
Usually 1 to 3 days. Your doctor will adjust the dose until your child has a soft stool each day.
Sources
- Evaluation and Treatment of Functional Constipation in Infants and Children (Tabbers et al.). ESPGHAN and NASPGHAN, J Pediatr Gastroenterol Nutr 2014;58(2):258-274. Checked 2026-09-18.
- Evaluation of Polyethylene Glycol Dosing for Functional Constipation in Children. Hospital Pharmacy, 2024 (PMC11497520). Checked 2026-09-18.
- WHO Child Growth Standards: weight-for-age percentiles, 0-24 months. World Health Organization, data files hosted by CDC/NCHS. Checked 2026-09-18.
- MiraLAX (polyethylene glycol 3350): Drug Facts. Bayer HealthCare, label via DailyMed. Checked 2026-09-25.