Miralax vs Colace

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For individuals experiencing constipation or irregular bowel movements, certain laxatives that alter the water balance in the intestines can help in managing symptoms and promoting regularity. Miralax and Colace are two such drugs that are commonly used for these digestive issues. They each have different mechanisms of action but both aim to ease stool passage.

Miralax is an osmotic-type laxative, working by holding water in the stool to soften it and increase the number of bowel movements. On the other hand, Colace falls under a class known as emollients or 'stool-softeners'. It works by increasing the amount of water absorbed by stools inside your intestines, making defecation easier. While both medications are designed to alleviate constipation, they do so through distinct methods.

What is Miralax?

Polyethylene glycol 3350 (the generic name for Miralax) is an over-the-counter osmotic laxative that helps to alleviate constipation by drawing water into the intestines, which softens the stool and induces bowel movements. It was first approved by the FDA in 1999. Miralax works by increasing the amount of water in your intestinal tract to stimulate bowel movements. It is primarily used for treating occasional episodes of constipation but can also be prescribed as a preparatory agent for colonoscopies.

On the other hand, Docusate sodium (the generic name for Colace) is a stool softener that increases the amount of water absorbed by your stools, making them softer and easier to pass through your body. While both drugs are effective at treating constipation, they work differently: Miralax functions as an osmotic laxative while Colace acts as a stool softener. This results in Miralax generally being more powerful and fast-acting than Colace, with fewer side effects such as bloating or cramping.

What conditions is Miralax approved to treat?

Miralax is approved for the treatment of different forms of constipation:

  • Occasional constipation
  • Chronic idiopathic constipation, which lacks a physical (anatomical) or physiological (hormonal or other body chemistry) explanation
  • Constipation related to certain medical conditions such as diabetes and Parkinson's disease

On the other hand, Colace acts primarily as a stool softener and is typically used for prevention rather than treatment. It can be utilized in cases like:

  • Prevention of dry, hard stools
  • Managing constipation due to various reasons including medications or prolonged bed rest.

How does Miralax help with these illnesses?

MiraLAX aids in managing constipation by drawing water into the colon, which softens the stool and stimulating bowel movement. It does this by introducing polyethylene glycol 3350, a non-absorbable substance that travels through the gut virtually unchanged. This allows water molecules to be retained within the stool, making it softer and easier to pass. On the other hand, Colace (docusate sodium) is a type of medicine called a stool softener. It works by increasing the amount of water that mixes with stool, which helps soften it and makes it easier to pass. Both medications are effective at relieving constipation; however, MiraLAX may work more quickly than Colace for some people as its action directly affects bulk-forming in stools rather than relying on liquid absorption.

What is Colace?

Colace, also known as docusate sodium, is a stool softener that works by increasing the amount of water absorbed by the stools in the gut. This action helps to soften the stools and make bowel movements easier, thus it's primarily used for prevention or treatment of constipation. Colace was first approved by the FDA many years ago and has been utilized extensively due to its gentle effect on the digestive system.

Unlike laxatives such as Miralax which increase intestinal activity to help move stools along more quickly, Colace does not cause this increased activity, making it less likely to lead to an urgent need for a bowel movement. Its main side effects are stomach cramps or upset but these tend not to be severe. The mild nature of Colace can be particularly beneficial for individuals with hemorrhoids or anal fissures who would benefit from softer stools.

What conditions is Colace approved to treat?

Colace, also known as docusate sodium, is a stool softener that has been approved for the treatment of certain conditions such as:

  • Occasional constipation
  • Prevention of dry, hard stools

It works by increasing the amount of water in your stool, making it softer and easier to pass. This medication can provide significant relief from discomfort associated with constipation and help maintain regular bowel movements.

How does Colace help with these illnesses?

Colace, or docusate sodium, is a type of stool softener that works by increasing the amount of water absorbed by the stools in the gut. This makes bowel movements softer and easier to pass, thereby relieving constipation. It is often used when straining to have a bowel movement should be avoided such as individuals recovering from surgery or childbirth. While Miralax is an osmotic-type laxative that helps increase the frequency of bowel movements by retaining water in the intestines and softening stools too, Colace distinguishes itself with its emollient properties which not only soften but also lubricate hard dry stools for more comfortable passage. Thus it may serve as an alternative for patients who do not respond well to osmotic laxatives like Miralax or they can be combined for more effective relief.

How effective are both Miralax and Colace?

Both Polyethylene Glycol 3350 (Miralax) and Docusate Sodium (Colace) have established histories of success in treating patients with constipation, and they were initially approved by the FDA only a few years apart. Since they act on different mechanisms to alleviate constipation, they may be prescribed under different circumstances. The effectiveness of Miralax and Colace in alleviating constipation was directly studied in several trials; both drugs exhibited similar efficacy in managing symptoms of constipation as well as similar safety profiles.

A review on Miralax demonstrated that it is effective from the first couple days of treatment, its side effect profile is generally mild compared to other laxatives, and it is well-tolerated even among elderly populations. This has led to Miralax becoming one of the most widely used over-the-counter treatments for occasional episodes of constipation.

On the other hand, meta-analysis studies indicated that Colace seems to be more effective than placebo at softening stools which aids bowel movements. Nonetheless, although it's commonly recommended for long-term use or prophylaxis against opioid-induced constipation due to its gentle action mechanism.

Significant research on Colace involves a combination regimen alongside stimulant laxatives such as Sennosides when dealing with severe cases of chronic idiopathic constipation or opioid-induced ones where stool softeners alone are insufficient. Despite their differences pharmacologically, both can provide relief for patients who experience infrequent bouts with irregularity or those needing assistance due to medications causing gastrointestinal issues like opioids leading towards chronic idiopathic or opioid-induced constipation respectively.

abstract image of a researcher studying a bottle of drug.

At what dose is Miralax typically prescribed?

Oral dosages of Miralax typically range from 17g to 34g per day, but studies have shown that a single dose of 17g/day is usually sufficient for relieving constipation in most adults and children over the age of 16. Children aged between one year old and sixteen may be started on smaller doses, as prescribed by their healthcare provider. If there's no response after several days, the dosage can be increased under medical supervision. The maximum dosage should not exceed more than two servings (34g) in any given day.

Meanwhile, Colace (docusate sodium), another medication used to treat constipation has different dosing guidelines. For adults and children over twelve years old, suggested oral dosage ranges from 50-300 mg daily which can be divided into one or multiple doses throughout the day depending upon severity of constipation. For children aged between two and twelve years old, recommended dosage is around 50-150 mg daily divided into multiple doses while for infants above six months it’s about10-40 mg daily.

Remember these are general guidelines; always consult with your healthcare professional before starting new medications or adjusting dosages since individual health conditions vary greatly.

At what dose is Colace typically prescribed?

Colace treatment generally starts at a dosage of 100 mg/day, taken by mouth. The dose can then be increased to 200 mg/day if necessary, divided into two doses, spaced approximately 12 hours apart. Maximum dose is typically 300 mg/day divided into three doses of 100 mg and spaced about 8 hours apart which may be tried if there is no response to the initial treatment after several days. However, it's important not to exceed this maximum recommended amount without consulting with your healthcare provider as prolonged use or excessive dosages could lead to dependency or changes in electrolyte balance.

What are the most common side effects for Miralax?

Common side effects of Miralax include:

  • Bloating
  • Gas
  • Upset stomach
  • Dizziness
  • Increased sweating

On the other hand, Colace might cause:

  • Stomach pain
  • Diarrhea
  • Cramping
  • A feeling of throat tightness or discomfort (rare)

Both medications have their own set of potential side effects; if you experience any severe or persistent symptoms while using either, it's important to seek immediate medical attention.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Miralax?

While MiraLAX and Colace are commonly regarded as safe, there can be potential side effects that patients should monitor for:

  • Any signs of allergic reactions: hives, difficulty breathing, swelling in your face or throat
  • Symptoms of severe electrolyte imbalance: headache, dizziness, feeling jittery; increased thirst or urination; constipation; irregular heartbeats; fluttering in your chest;
  • Unusual changes in mood or behavior (confusion, depression)
  • Bloody or tarry stools
  • Painful or difficult urination
  • Severe stomach pain which may spread to your back
  • Nausea with loss of appetite and weight loss

If any of these symptoms manifest while using either MiraLAX or Colace it is crucial to seek immediate medical attention. It's also important to note that long-term use of laxatives can lead to dependency and chronic constipation.

What are the most common side effects for Colace?

Common side effects of Colace may include:

  • Stomach pain or cramping
  • Nausea, vomiting
  • Loss of appetite
  • Diarrhea or loose stools
  • Throat irritation when swallowing the tablet
  • Mild skin rash.

It's important to note that while these side effects can be unpleasant, they are usually temporary and subside as your body adjusts to the medication. However, if you experience severe or persistent symptoms, it's crucial to seek medical attention immediately.

Are there any potential serious side effects for Colace?

While Colace is generally safe and well-tolerated, there are some potential side effects that might indicate a serious reaction. Be aware of:

  • Signs of an allergic response: hives, itching, difficulty breathing or swallowing, swelling in your face or throat
  • Unusual weakness or tiredness
  • Irregular heartbeat
  • Persistent nausea or vomiting
  • Severe stomach/abdominal pain
  • Blood/mucus in your stool

These symptoms are rare but can signify a more serious problem. If you experience any of these after taking Colace, discontinue use immediately and consult with your healthcare provider as soon as possible.

Contraindications for Miralax and Colace?

Both Miralax and Colace, along with most other laxatives, may worsen symptoms of bowel obstruction in some people. If you notice your constipation worsening or an increase in abdominal pain, nausea or vomiting, please seek immediate medical attention.

Neither Miralax nor Colace should be taken if you have been diagnosed with a bowel obstruction. Always tell your physician which medications you are taking; certain conditions such as kidney disease might require special dosage instructions or caution due to the risk associated with increased mineral levels from these medications. Similarly, prolonged use can cause electrolyte imbalances which may interact dangerously with specific heart medications.

How much do Miralax and Colace cost?

For the brand name versions of these drugs:

  • The price for 30 doses of Miralax (17g/dose) averages around $25, which works out to roughly $0.83 per day.
  • The price for 60 capsules of Colace (100mg/capsule) is about $15, working out to approximately $0.50 per day.

Thus, if you are taking the single daily recommended dose, then brand-name Colace is less expensive on a per-day treatment basis compared to Miralax. Keep in mind that cost should not be your primary consideration when deciding on the right medication for you.

As for their generic counterparts,

  • Polyethylene Glycol 3350 (the active ingredient in Miralax), costs range from as low as $10-$20 for a container with about a month's supply ($0.33-$0.67/day).
  • Docusate Sodium (the active ingredient in Colace), costs vary significantly depending on whether it’s liquid or capsule form but could be as low as about $7-$14 for a typical month-long supply ($0.23 - $0.47/day).

Both generic options offer significant savings and are equally effective at relieving constipation compared to their branded equivalents.

Popularity of Miralax and Colace

Polyethylene glycol 3350, known by its brand name Miralax, was estimated to have been prescribed to about 4.5 million people in the US in 2020. This stool softener accounted for just over 15% of laxative prescriptions in the US and has been generally increasing in prevalence since it became available over-the-counter.

Docusate, commonly recognized as Colace among other brands, followed closely behind with around 3.8 million prescriptions filled out during the same year. In the USA, docusate accounts for about 12% of all laxative prescriptions but unlike Miralax has seen a gradual decrease in usage over recent years due to rising popularity of other over-the-counter options like polyethylene glycol-based products.


Both Miralax (polyethylene glycol 3350) and Colace (docusate sodium) have a long-standing record of usage in patients suffering from constipation, with numerous clinical studies indicating their effectiveness. While both drugs can be used independently, they may also sometimes be combined under the careful consideration of a healthcare provider. Due to their different mechanisms of action — Miralax acting as an osmotic agent that retains water in the stool to soften it and increase bowel movements, while Colace is a stool softener that increases the amount of water absorbed by the stools — they tend to be prescribed under different circumstances.

Miralax is often considered a first-line treatment option for short-term relief or occasional constipation, whereas Colace would usually be considered as an addition to other treatments or in patients who should avoid straining during bowel movements due to certain health conditions like heart problems or after certain types of surgery.

Both laxatives are available over-the-counter without prescription which represents significant cost savings especially for patients who must pay out-of-pocket. Both Miralax and Colace may require some time before effects become noticeable.

The side effect profiles are similar between these two drugs; both being generally well-tolerated but can cause bloating, gas, upset stomach or diarrhea if consumed at high doses. For both drugs, users should monitor their bowel activity closely when starting treatment and seek medical attention immediately if severe pain or rectal bleeding occurs.