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Kristalose Coupon - Kristalose 30 packets of 20g carton

Kristalose

lactulose
Used for Constipation

Kristalose (lactulose) is an osmotic laxative. It's used to help relieve constipation in adults. Kristalose (lactulose) comes as a powder packet with 10 grams of lactulose per packet. The usual dosage is to dissolve 1 to 2 packets of Kristalose (lactulose) in water and to take by mouth daily. After you start treatment, it can take up to two days before you have a bowel movement. Some common side effects of Kristalose (lactulose) include stomach cramps and passing gas.

Reviewed by:
reviewerAllison Gourley, PharmD
reviewerKristianne Hannemann, PharmD
Last reviewed on June 5, 2024
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What is Kristalose (lactulose)?

What is Kristalose (lactulose) used for?

How Kristalose (lactulose) works

Kristalose (lactulose) is an osmotic laxative. It eases constipation by drawing more fluid into the gut. This helps soften the stool and makes it easier to pass.

Drug facts

Common BrandsKristalose
Drug ClassOsmotic laxative
Controlled Substance ClassificationNot a controlled medication
Generic StatusNo lower-cost generic available
AvailabilityPrescription only
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Side effects of Kristalose (lactulose)

The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

Common Side Effects

  • Flatulence or passing gas
  • Stomach cramps

Less Common Side Effects

  • Nausea or vomiting
  • Diarrhea

Source: DailyMed

The following Kristalose (lactulose) side effects have also been reported

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

For bulk-forming-containing

Difficulty in breathing

intestinal blockage

skin rash or itching

swallowing difficulty (feeling of lump in throat)

For hyperosmotic-containing

Confusion

dizziness or light-headedness

irregular heartbeat

muscle cramps

unusual tiredness or weakness

For stimulant-containing

Confusion

irregular heartbeat

muscle cramps

pink to red, red to violet, or red to brown coloration of alkaline urine (for cascara, danthron, and/or senna only)

skin rash

unusual tiredness or weakness

yellow to brown coloration of acid urine (for cascara, and/or senna only)

For stool softener (emollient)-containing

Skin rash

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For hyperosmotic-containing

Bloating

cramping

diarrhea

nausea

gas

increased thirst

For lubricant-containing

Skin irritation surrounding rectal area

For stimulant-containing

Belching

cramping

diarrhea

nausea

For stool softener (emollient)-containing

Stomach and/or intestinal cramping

throat irritation (liquid forms only)

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

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Pros and cons of Kristalose (lactulose)

Pros

  • Comes as convenient single-dose packets
  • Might be a good option for people with constipation who didn’t see benefits with OTC laxatives
  • Typically taken once daily

Cons

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Pharmacist tips for Kristalose (lactulose)

pharmacist
  • You need to mix the Kristalose (lactulose) powder packet in water before taking it. Each packet should be mixed in half a glass (4 ounces) of water. After it's mixed, the solution should be colorless to a slightly pale yellow color.
  • Talk with your healthcare team if you've questions about how Kristalose (lactulose) might affect your blood sugar. Kristalose (lactulose) does contain galactose and lactose, which are two types of sugars. But limited research shows that Kristalose (lactulose) isn't likely to raise your blood sugar levels.
  • Kristalose (lactulose) might cause diarrhea if your dose is too high. This can cause you to lose water and feel dehydrated, so make sure you drink enough fluids to make up for the loss. If you have diarrhea, let your healthcare team know. They can lower your dose of Kristalose (lactulose) and let you know if you need more medical attention.
  • Make sure to tell your healthcare team if you're lactose intolerant. Kristalose (lactulose) contains lactose, which might cause people with this condition to have bloating, cramping, and diarrhea.
  • Don’t take antacids, like Mylanta Maximum Strength (aluminum hydroxide / magnesium hydroxide / simethicone) or calcium carbonate (Tums), at the same time as Kristalose (lactulose). They might cause Kristalose (lactulose) to not work as well. If you need medications for heartburn, ask your healthcare team about other options that won't interact with Kristalose (lactulose).
  • There aren't enough studies about whether Kristalose (lactulose) is safe during pregnancy. But Kristalose (lactulose) might not be appropriate to take during pregnancy because it can cause nausea and bloating, which can be very uncomfortable. If you have plans to get pregnant, ask your healthcare team about safer options to treat constipation.
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Common questions about Kristalose (lactulose)

If you have high blood sugar, you’ll want to make sure that you're checking your blood sugars while taking Kristalose (lactulose). Kristalose (lactulose) contains galactose and lactose, which are both forms of sugar. Limited research shows that Kristalose (lactulose) doesn't seem to cause a spike in blood sugar, but it is still recommended to check blood sugar levels just in case.

You can eat after taking Kristalose (lactulose), especially if the medication causes you to feel nauseous or vomit. Food can help you feel less queasy after taking a dose.

The makers of Kristalose (lactulose) recommend dissolving the medication in water. Other brand name or generic versions of lactulose solution are okay to mix with fruit juice or milk to help with the taste. If you're having trouble tolerating the taste of Kristalose (lactulose), speak with your healthcare team.

Like lactulose, Kristalose (lactulose) can cause similar side effects. Because your gut doesn't absorb Kristalose (lactulose), it can cause uncomfortable side effects like gas, bloating, and cramps.

Kristalose (lactulose) and polyethylene glycol (Miralax) are both osmotic laxatives that treat constipation, but they're not the same. One main difference is that Kristalose (lactulose) is available by prescription only, while polyethylene glycol (Miralax) can be found over the counter. Another difference is people typically have a bowel movement within 2 days of taking Kristalose (lactulose), but it might take up to 3 days to have a bowel movement after taking Kristalose (lactulose). Lastly, polyethylene glycol (Miralax) is less likely to cause side effects than lactulose, so healthcare professionals (HCPs) might recommend polyethylene glycol (Miralax) over Kristalose (lactulose). Talk with your HCP if you've more questions about the differences of these medications.

No, Kristalose (lactulose) is only available with a prescription from your healthcare professional (HCP). If you're looking for an OTC option to treat your constipation, ask your healthcare team about what options might be appropriate for you.

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Risks and warnings for Kristalose (lactulose)

Kristalose (lactulose) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.

Loss of fluids

  • Risk factors: Taking Kristalose (lactulose) for more than 6 months | Age 65 years and older | Taking medications that cause electrolyte imbalances

Kristalose (lactulose) can make you dehydrated which can affect your body's mineral levels. Electrolytes (minerals), such as sodium, potassium, and calcium, have many important functions in the body. Your healthcare professional (HCP) might want to check these regularly while you're taking Kristalose (lactulose), especially if you’re older in age or have been taking Kristalose (lactulose) for a long period of time. Call your HCP right away if you feel extremely thirsty, tired, or confused because these are signs that Kristalose (lactulose) might be making you dehydrated and affecting your electrolyte levels.

Possible risk of high blood sugar

  • Risk factors: Diabetes

Be mindful that Kristalose (lactulose) contains galactose and lactose, which are both forms of sugar. If you have high blood sugar, it's best to check your blood sugar levels regularly while taking Kristalose (lactulose). Limited research shows that Kristalose (lactulose) doesn't seem to cause a spike in blood sugar, but you're still recommended to check your blood sugar levels just in case.

Problems during colonoscopy

If you're planning to have a colonoscopy or a rectal exam, let your healthcare team know you're taking Kristalose (lactulose). Your HCP might have you take different medications to clean out your gut before your exam.

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Kristalose (lactulose) dosage

The average cost for 1 carton of 30 packets of 20g of Kristalose (lactulose) is $107.97 with a free GoodRx coupon. This is 71.91% off the average retail price of $384.42.
cartonCarton
DosageQuantityPrice as low asPrice per unit
30 packets of 10g1 carton$104.49$104.49
30 packets of 20g1 carton$107.97$107.97
packetPacket
DosageQuantityPrice as low asPrice per unit
10g30 packets$104.49$3.48

Typical dosage for Kristalose (lactulose)

Each Kristalose (lactulose) packet either contains 10 or 20 grams of lactulose. To prepare, each packet needs to be dissolved in 4 oz of water.

The typical dose is to dissolve 1 to 2 packets of Kristalose (lactulose) in water and then to take by mouth daily. The maximum recommended dose is 40 grams daily.

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Interactions between Kristalose (lactulose) and other drugs

Kristalose (lactulose) may interact with certain medications or supplements. Always let your doctor and pharmacist know about any other medications or supplements (including prescribed and over-the-counter medications, vitamins, and dietary or herbal supplements) that you are currently taking. The list below does not include all possible drug interactions with Kristalose (lactulose). Please note that only the generic name of each medication is listed below.

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking any of these medicines, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using medicines in this class with any of the following medicines is not recommended. Your doctor may decide not to treat you with a medication in this class or change some of the other medicines you take.

Using medicines in this class with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

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Kristalose (lactulose) contraindications

Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Kristalose (lactulose) will not be safe for you to take.

  • People who need a low-galactose diet
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What are alternatives to Kristalose (lactulose)?

There are a number of medications that your doctor can prescribe in place of Kristalose (lactulose). Compare a few possible alternatives below.
Kristalose (lactulose)
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$104.49Lowest GoodRx priceView prices
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$7.98Lowest GoodRx priceView prices
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$4.63Lowest GoodRx priceView prices
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References

Best studies we found

Bosch, A. M. (2011). Classic galactosemia: Dietary dilemmas. Journal of Inherited Metabolic Disease.

Chartwell RX, LLC. (2024). Lactulose solution [package insert]. DailyMed.

Cumberland Pharmaceuticals Inc. (2018). Kristalose- lactulose powder, for solution [package insert]. DailyMed.

GoodRx Health has strict sourcing policies and relies on primary sources such as medical organizations, governmental agencies, academic institutions, and peer-reviewed scientific journals. Learn more about how we ensure our content is accurate, thorough, and unbiased by reading our editorial guidelines.

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