Compare Fibercon vs. Miralax

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

Fibercon
(calcium polycarbophil)

Miralax
(polyethylene glycol)

Helps get things moving. Fibercon (Calcium Polycarbophil) is a natural fiber laxative that's safe enough to take during pregnancy. Just make sure you take it with plenty of liquid.Helps get things moving. Miralax (Polyethylene Glycol) provides effective relief of constipation without "cramping" your style.
Reviews & ratings
Filter group. All currently selected
Filter group. All currently selected
3.96Fibercon
Reviews for Fibercon
45%
of people (All ages) say Fibercon is worth it
28%
say it works well
21%
say it's a big hassle
Have you used Fibercon (calcium polycarbophil)?
Worth itNot sureNot worth it
Reviews for Miralax
75%
-30% worse vs. Fibercon
54%
-26% worse vs. Fibercon
10%
-11% worse vs. Fibercon
226 reviews
Have you used Miralax (polyethylene glycol)?
Worth itNot sureNot worth it
Side effects
FiberconMiralax

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

FDA side effect reports for Fibercon »

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

More about Miralax side effects »
How it works
FiberconMiralax
Fibercon (Calcium Polycarbophil) is a fiber-based laxative. It adds bulk and moisture to your intestine, which softens stool and makes it easier to pass.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
FiberconMiralax
Over-the-counterOver-the-counter
Available as
FiberconMiralax
  • Pill
  • Liquid
Used for
FiberconMiralax
Risk factors for serious side effects
FiberconMiralax
  • Taking with calcium supplements
  • Taking with oral bisphosphonates
  • Age 60 or older
  • Malignancy
  • Other condition that causes blockage or narrowing of bowel
Detailed Fibercon (calcium polycarbophil) risks & warnings »
  • Taking with medications that cause electrolyte imbalance
  • Age 60 or older
  • Women of childbearing age
  • Malignancy
Detailed Miralax (polyethylene glycol) risks & warnings »
Pregnancy

The FDA hasn’t classified this medicine’s effects on unborn babies. Talk with your doctor about this medicine if you’re pregnant or planning on it.

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
FiberconMiralax
  • Talk to you doctor about eating certain foods and getting more exercise to help prevent your constipation.
  • Talk to you doctor about eating certain foods and getting more exercise to help prevent your constipation.
Pain
FiberconMiralax
  • If you take Fibercon then have chest pain, vomiting, trouble breathing or swallowing, get medical help immediately.
  • Ask your doctor before taking Fibercon if you have stomach pain, nausea, vomiting or had sudden changes in your stool for more than 2 weeks.
No pain related info.
Weight
FiberconMiralax
  • Less gas and bloating compared to psyllium laxative products.
  • Doesn't cause as much bloating, cramping or feelings like you "have to go right now" as other medicines to treat constipation.
  • 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.
Upsides and benefits
FiberconMiralax
  • Some people felt Fibercon was a hassle but still worth it.
  • It's safe to use short-term during pregnancy and breast-feeding as long as you take it with plenty of liquid, but you should still check with your baby doctor first.
  • Less gas and bloating compared to psyllium laxative products.
  • 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
FiberconMiralax
  • You may have to take Fibercon daily for 1-3 days to see full effects.
  • If you don't take it with enough liquid, it could swell and block your throat and cause choking.
  • Not the best choice for people who have swallowing problems or aren't able to drink lots of liquids.
  • Can cause heartburn, gas, and belly cramps.
  • 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
FiberconMiralax
  • It's important to take each dose with at least 8 ounces (a full glass) of water or other liquid. Works in about 12-72 hours.
  • Don't take more than 8 caplets in a 24 hour period without asking your doctor first and not for more than one week.
  • Don't take Fibercon within 2 hours before or after taking other medicines. It may interact and affect how they work.
  • If you take Fibercon then have chest pain, vomiting, trouble breathing or swallowing, get medical help immediately.
  • Ask your doctor before taking Fibercon if you have stomach pain, nausea, vomiting or had sudden changes in your stool for more than 2 weeks.
  • Ask your doctor about giving Fibercon to anyone younger than 12 years.
  • Talk to you doctor about eating certain foods and getting more exercise to help prevent your constipation.
  • 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 FiberconSide effectsReviews & ratingsAlternativesFDA package insert
Have you used Fibercon (calcium polycarbophil)?
Worth itNot sureNot worth it
More about MiralaxSide effectsReviews & ratingsAlternativesFDA package insert
Have you used Miralax (polyethylene glycol)?
Worth itNot sureNot worth it