PEG 3350 (polyethylene glycol 3350): what it does and how to use it

PEG 3350 is an osmotic laxative many people use for occasional constipation. It pulls water into the bowel to soften stool and make passing easier. People choose it because it’s gentle compared with stimulant laxatives and doesn’t usually cause harsh cramping.

How PEG 3350 works and dosing basics

The common adult dose is 17 grams of powder (one capful) mixed in about 4–8 ounces of water, taken once a day. Most users notice results in 1–3 days. That timing matters—if nothing changes after three days, check with a clinician instead of increasing the dose yourself.

For kids, dosing varies by age and weight. Many pediatricians recommend a reduced amount or specific split doses. Never give PEG 3350 to a child without asking a pediatrician first and follow exact instructions for measuring the powder.

PEG 3350 is minimally absorbed into the bloodstream, so it has very few drug interactions. Still, tell your doctor about other medicines, especially if you use diuretics or have conditions affecting fluids and electrolytes.

Safety, side effects, and smart tips

Typical side effects are mild: bloating, gas, mild cramps, and sometimes loose stools. Stop and seek care if you get severe abdominal pain, fever, or bloody stools. Those can be signs of a serious problem like a bowel blockage or infection.

Older adults should be cautious. If diarrhea becomes heavy, dehydration and electrolyte imbalance are possible. Drink extra fluids and contact a provider if you feel dizzy, weak, or confused. People with bowel obstruction, severe inflammatory bowel disease, or known allergy to PEG should avoid it.

Pregnant or breastfeeding? Many clinicians consider PEG 3350 low risk, but check with your caregiver to be safe. If you have kidney disease or heart failure, ask about monitoring before you start.

Use PEG 3350 short term unless a doctor advises otherwise. Chronic constipation needs a medical check to find causes like medication side effects, low fiber intake, or underlying conditions. Relying on laxatives long term without guidance can mask issues.

Want fewer trips to the pharmacy? Try to boost fiber slowly to 20–30 grams daily, increase water, and move more. A simple routine—trying to go after breakfast—can help your bowel follow a schedule. If fiber causes gas, lower the amount and increase slowly.

Where to buy it: PEG 3350 is available over the counter in many countries under names like Miralax. Buy from reputable pharmacies or well-known online stores, check the label for the dosing scoop, and avoid unknown sellers. If you’re unsure whether PEG 3350 is right for you, your pharmacist can give quick, practical advice.

If questions remain about dosing or safety for your situation, ask your doctor or pharmacist. They can help adjust the plan or suggest alternatives that fit your health needs.