Compare Lactulose vs. Miralax

Head-to-head comparisons of medication uses, side effects, ratings, and more.

Generlac
(lactulose)

Miralax
(polyethylene glycol)

Coming soon.Helps get things moving. Miralax (Polyethylene Glycol) provides effective relief of constipation without "cramping" your style.
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Best available price for 900 (10g/15ml) oral solutions of lactulose
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Reviews & ratings
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Reviews for Generlac (lactulose)
Not enough review data. Review it!
of people (All ages) say Generlac (lactulose) is worth it
Not enough review data. Review it!
say it works well
Not enough review data. Review it!
say it's a big hassle
Have you used Generlac (lactulose)?
Worth itNot sureNot worth it
Reviews for Miralax (polyethylene glycol)
75%
-25% worse vs. Generlac (lactulose)
54%
-46% worse vs. Generlac (lactulose)
10%
-10% worse vs. Generlac (lactulose)
226 reviews
Have you used Miralax (polyethylene glycol)?
Worth itNot sureNot worth it
Side effects
LactuloseMiralax

We haven’t found good data for Lactulose side effects.

FDA side effect reports for Lactulose »

The Miralax FDA package insert doesn’t have numbers about how common side effects are.

More about Miralax side effects »
How it works
LactuloseMiralax
Coming soon.Miralax (Polyethylene Glycol) is an osmotic laxative. It uses osmosis to keep more water in your intestine, which softens your stool and makes it easier to pass.
Type of medication
LactuloseMiralax
Over-the-counter
Available as
LactuloseMiralax
  • Liquid
  • Liquid
Used for
LactuloseMiralax
  • Constipation Hepatic Encephalopathy Treatment And Prophylaxis
Risk factors for serious side effects
LactuloseMiralax
    Coming soon.
    • Taking with medications that cause electrolyte imbalance
    • Age 60 or older
    • Women of childbearing age
    • Malignancy
    Detailed Miralax (polyethylene glycol) risks & warnings »
    Pregnancy

    Research studies with animals haven’t found a risk to unborn babies, but it hasn’t been properly studied in humans.

    Research studies with animals found harmful effects on unborn babies. It hasn’t been properly studied in humans. The benefits might outweigh the risks even if you’re pregnant. Talk with your doctor.

    Food
    LactuloseMiralax
    No food related info.
    • Talk to you doctor about eating certain foods and getting more exercise to help prevent your constipation.
    Weight
    LactuloseMiralax
    No weight related info.
    • It causes little to no cramping, bloating, gas, or feelings like you "have to go right now" compared to some other medicines to treat constipation.
    • Doesn't cause as much bloating, cramping or feelings like you "have to go right now" as other medicines to treat constipation.
    Upsides and benefits
    LactuloseMiralax
    Coming soon
    • Miralax is the most recommended laxative by pharmacists and doctors.
    • Most people felt it was worth the hassle.
    • It's gluten and sugar free.
    • It causes little to no cramping, bloating, gas, or feelings like you "have to go right now" compared to some other medicines to treat constipation.
    • Works differently than other over-the-counter laxatives so it's a great alternative if other medicines haven't worked.
    Downsides and risks
    LactuloseMiralax
    Coming soon
    • You have to dissolve Miralax in a beverage and drink it versus taking a pill.
    • It's not for children 16 years or younger.
    • Miralax doesn't work overnight. It can take up to 2-4 days to have a bowel movement.
    • It's not recommended that you take it for more than a week, so it you haven't had any success, you'll need to call your doctor for other laxative options.
    Tips from our pharmacists for people taking the medication
    LactuloseMiralax
    Coming soon
    • Dissolve Miralax powder in 4 to 8 ounces of water, juice or other drink (cold or hot) once a day.
    • Works in about 1 to 3 days. Don't use for more than 1 week.
    • Miralax is available in four different size dose bottles. It also come in pre-measured single-dose packets to make dosing easier or if you travel.
    • Ask your doctor about giving it to anyone younger than 17 years.
    • Doesn't cause as much bloating, cramping or feelings like you "have to go right now" as other medicines to treat constipation.
    • Ask your doctor before you take Miralax if you have nausea or vomiting, irritable bowel syndrome (IBS), kidney disease, or sudden changes in your stool for more than 2 weeks.
    • Stop using Miralax and call your doctor if you have pain, cramping, swelling or bulging in your belly, diarrhea, rectal bleeding or find you need to use for more than 1 week.
    • Talk to you doctor about eating certain foods and getting more exercise to help prevent your constipation.
    Learn more
    More about LactuloseSide effectsReviews & ratingsFDA package insert
    Have you used Generlac (lactulose)?
    Worth itNot sureNot worth it
    More about MiralaxSide effectsReviews & ratingsAlternativesFDA package insert
    Have you used Miralax (polyethylene glycol)?
    Worth itNot sureNot worth it