Lactulose vs Amitiza

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For patients suffering from chronic idiopathic constipation or other types of bowel irregularities, certain medications can help in promoting regular bowel movements and alleviating discomfort. Lactulose and Amitiza are two such drugs that are commonly prescribed for these conditions. They each function differently within the digestive system, but both have demonstrated effectiveness in aiding regular bowel activity. Lactulose is a synthetic sugar used to treat constipation by softening the stool and increasing its water content; it acts by drawing water into the intestine to facilitate defecation. On the other hand, Amitiza (Lubiprostone) is classified as a chloride channel activator which increases fluid secretion in your intestines enabling easier passage of stools.

What is Lactulose?

Lactulose, a synthetic sugar used in the treatment of constipation and to treat or prevent complications of liver disease (hepatic encephalopathy), was first approved by the FDA in 1976. It works by drawing water into the bowel, which softens stools and stimulates bowel movements. Lactulose is generally well-tolerated but can cause side effects such as bloating, gas, and diarrhea.

On the other hand, Lubiprostone (the generic name for Amitiza) represents a newer class of drugs known as chloride channel activators. Approved by the FDA in 2006, Amitiza increases fluid secretion in your intestines to help make it easier to pass stools. It's prescribed primarily for chronic idiopathic constipation and irritable bowel syndrome with constipation. While Amitiza has shown effectiveness without many of lactulose's gassy side effects, it can still trigger nausea or diarrhea in some people.

What conditions is Lactulose approved to treat?

Lactulose is approved for the treatment of different conditions, including:

  • Chronic constipation
  • Prevention and treatment of portal-systemic encephalopathy (PSE), also known as hepatic encephalopathy – a complication associated with severe liver disease

On the other hand, Amitiza has been approved to treat:

  • Chronic idiopathic constipation in adults
  • Opioid-induced constipation in adults with chronic non-cancer pain
  • Irritable bowel syndrome with constipation (IBS-C) in women aged 18 years or older.

How does Lactulose help with these illnesses?

Lactulose aids in managing constipation by increasing the amount of water in the intestines. It does this by drawing water into the colon from other body tissues, which helps to soften stools and stimulate bowel movements. Water is a fundamental component of our bodies that plays an important role not just in hydration but also digestion, nutrient absorption, and waste elimination among other things. In individuals with constipation, it's thought that their stool has relatively lower levels of moisture making them hard and difficult to pass. Therefore, by increasing water content in the intestines, Lactulose can improve bowel regularity and help patients manage their condition effectively.

What is Amitiza?

Amitiza is a brand name for lubiprostone, which is a chloride channel activator. This means it increases the secretion of fluid in the intestines to promote bowel movements. Amitiza was first approved by the FDA in 2006 and primarily used for treating chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation (IBS-C). Unlike lactulose, which works by drawing water into the colon to soften stools and increase stool frequency, Amitiza directly impacts intestinal fluid secretion without causing electrolyte imbalance. The unique way it functions means that its side effect profile differs from that of traditional laxatives like lactulose. Specifically, while bloating and gas are common side effects of lactulose, they are less commonly associated with Amitiza use. In addition, some patients may find Amitiza more effective if they have not had satisfactory results from other constipation treatments like lactiva.

What conditions is Amitiza approved to treat?

Amitiza is a prescription medication that has been approved by the FDA for the treatment of:

  • Chronic idiopathic constipation
  • Opioid-induced constipation (OIC) in adults with chronic, non-cancer pain
  • Irritable bowel syndrome with constipation (IBS-C) in women over 18 years old

How does Amitiza help with these illnesses?

Amitiza, like lactulose, is a medication used to treat constipation. It works by increasing the secretion of chloride in the intestines which results in increased fluid and softens the stool, thereby facilitating its passage through the bowel. This mechanism of action differs from lactulose that essentially draws water into the colon to soften stools. Amitiza's unique action on chloride channels not only makes it effective for chronic idiopathic constipation but also for Irritable Bowel Syndrome with predominant constipation (IBS-C). Furthermore, unlike lactulose, Amitiza does not cause significant bloating or gas - common side effects associated with lactulose usage. Hence, Amitiza may be preferred when patients do not respond well to traditional laxatives such as lactulose or when they experience intolerable adverse reactions.

How effective are both Lactulose and Amitiza?

Both lactulose and lubiprostone (Amitiza) are well-established medications used in the management of constipation, having been approved by the FDA several years apart. Lactulose is a synthetic sugar that works by drawing water into the intestines to help soften stools while lubiprostone increases fluid secretion in your intestines to improve stool passage. Both have shown efficacy in managing symptoms of chronic idiopathic constipation.

The effectiveness of lactulose and lubiprostone was compared directly in clinical trials; both drugs demonstrated similar potential for alleviating symptoms of constipation as well as similar safety profiles. In these studies, no significant differences were found between patients receiving lactulose or those receiving lubiprostone when measuring metrics related to bowel movement frequency and consistency.

Lubiprostone has a unique mechanism that involves activating chloride channels on cells lining your small intestine, which promotes movement through the gut, making it particularly effective against certain types of drug-induced or chronic idiopathic constipation where other treatments might fail. However, its use may be limited due to higher cost compared to other options like lactulose.

On the other hand, a 2004 review reported that lactulose offers an affordable solution with generally mild side-effects such as bloating and gas but can cause diarrhea if not correctly dosed. It's also safe enough for long-term use, even during pregnancy or breastfeeding when many other medications are contraindicated.

Therefore whether you're prescribed Amitiza or Lactulose will depend on various factors including severity and type of your condition along with personal health history.

abstract image of a researcher studying a bottle of drug.

At what dose is Lactulose typically prescribed?

Lactulose dosages typically range from 15-60 ml/day, although studies have shown that a dose of 15ml/day is usually adequate for treating constipation in most individuals. For Amitiza (lubiprostone), the dosage recommended for chronic idiopathic constipation and irritable bowel syndrome with constipation in adults is 24 micrograms twice daily. Dosage may be reduced after a few weeks based on response and tolerability. In any case, exceeding the maximum recommended dosage could lead to adverse reactions and hence it should not be exceeded.

At what dose is Amitiza typically prescribed?

Treatment with Amitiza is generally commenced at a dose of 24 mcg twice daily for chronic idiopathic constipation and irritable bowel syndrome, or 8 mcg twice daily for opioid-induced constipation. The dosage can then be adjusted based on individual patient's response, but it should not exceed the recommended starting dose. Administering Amitiza doses spaced 12 hours apart is usually effective in managing symptoms. However, if there's no significant improvement after two weeks of treatment, you may need to consult your healthcare provider about adjusting the dosage or considering alternative treatments.

What are the most common side effects for Lactulose?

Common side effects of lactulose may include:

  • Bloating
  • Diarrhea
  • Gas and flatulence
  • Nausea, vomiting
  • Stomach cramps or discomfort

While Amitiza is known to cause side effects such as:

  • Nausea, which can be severe at times
  • Headache
  • Diarrhea
  • Abdominal pain or discomfort
  • Swelling in hands or feet (edema)
  • Dizziness and fainting -Fatigue

Always consult with a healthcare provider for any persistent or worrisome symptoms.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Lactulose?

In rare cases, lactulose can cause potentially serious side effects. Here are some symptoms to be aware of:

  • Signs of severe allergic reaction or anaphylaxis: difficulty breathing, swelling in your face or throat, hives
  • Severe stomach pain and diarrhea
  • An unusual heartbeat or pulse rate; palpitations
  • Significant weight loss without trying
  • Dehydration symptoms - feeling very thirsty or hot, being unable to urinate, heavy sweating, hot and dry skin
  • Electrolyte imbalance – headache with chest pain and severe dizziness (feeling like you might pass out), fast or pounding heartbeats;

Amitiza also has potential for serious side effects which include:

  • Chest tightness or trouble breathing shortly after taking Amitiza.
  • Diarrhea that is severe.
  • Swelling hands/legs/feet;

If you experience any of these symptoms while using either medication, seek medical attention immediately.

What are the most common side effects for Amitiza?

Amitiza, when compared to Lactulose, has some distinctive side effects that patients should be aware of:

  • Nausea is one of the most common side effects; it may become less severe over time as your body adjusts.
  • Diarrhea and stomach pain are also frequently reported.
  • Headache and dizziness can occur.
  • Rarely, shortness of breath or chest tightness may manifest immediately after taking Amitiza. This typically occurs within an hour after your first dose but could occur later.
  • Some people experience excessive sweating or a flushed face.

It's important to note that while these side effects can seem daunting, many people take Amitiza without experiencing any negative reactions. As with any medication decision, you should weigh the benefits against the potential risks in consultation with your healthcare provider.

Are there any potential serious side effects for Amitiza?

While Amitiza is generally well-tolerated, some users might experience more severe side effects that require immediate medical attention. These can include:

  • Signs of an allergic reaction such as hives; difficulty breathing; swelling of your face, lips, tongue, or throat
  • Difficulty in swallowing or feelings of tightness in the chest
  • Severe nausea or diarrhea
  • Shortness of breath within 1 hour after taking the medication
  • Pounding heartbeats or fluttering in your chest
  • Confusion, mood changes, unusual thoughts or behavior

If you experience any of these symptoms after starting treatment with Amitiza, stop using the drug and seek emergency medical assistance immediately.

Contraindications for Lactulose and Amitiza?

Both Lactulose and Amitiza, along with most other medications for constipation, may worsen symptoms in some people. If you notice your constipation worsening, or an increase in abdominal pain or bloating, please seek immediate medical attention.

Neither Lactulose nor Amitiza should be taken if you have a blockage in your bowel (intestinal obstruction), severe diarrhea, or conditions that could lead to electrolyte imbalance. Always inform your physician about which medications you are taking; certain drugs like those reducing stomach acid can interfere with the effectiveness of these treatments.

Also noteworthy is that long-term use of laxatives like lactulose can sometimes lead to dependence on them for normal bowel movements. Prolonged use might also cause electrolyte imbalances resulting from excessive water loss through stools.

Before starting any new medication regimen involving either lactulose or Amitiza, it's important to communicate openly with your healthcare provider about all over-the-counter products and prescription medicines currently being used as well as any underlying health conditions.

How much do Lactulose and Amitiza cost?

For the brand name versions of these drugs:

  • The price of a 473 ml bottle of Lactulose (10 g/15 ml) averages around $30, which works out to roughly $0.63–$1.26/day, depending on your dose.
  • The price for 60 capsules of Amitiza (24 mcg) is about $250, working out to approximately $4.16/day.

Thus, if you are in the higher dosage range for lactulose (i.e., 30 ml per day or higher), then Amitiza can be less expensive on a per-day treatment basis at its lower dosages (8mcg twice daily). Please note that cost should not be a primary consideration in determining which of these drugs is right for you.

For generic versions of lactulose and Amitiza (lubiprostone), costs vary:

  • Generic lactulose syrup is available in bottles varying from 120ml up to 1000ml with approximate costs ranging between $.20 - .40 cents per day based on standard dosage recommendations.
  • Lubiprostone has no generic form currently available; as such the cost remains relatively high at around $4/day even when considering different suppliers and potential discounts through insurance providers.

Popularity of Lactulose and Amitiza

Lactulose, a synthetic sugar used in the treatment of constipation and hepatic encephalopathy, was estimated to have been prescribed to about 2.5 million people in the US in 2020. Lactulose accounted for just over 11% of laxative prescriptions in the US. The use of lactulose has generally remained steady since it first became popularly prescribed.

On the other hand, Lubiprostone (brand name Amitiza), which is utilized for relieving chronic idiopathic constipation and irritable bowel syndrome with constipation (IBS-C), was prescribed to approximately 1 million people in the USA during that same year. In comparison to overall laxative prescriptions within the country, lubiprostone accounts for around 4%. Its prevalence has seen a slight increase over recent years due its efficacy and because it offers an option for patients who do not respond well or cannot tolerate other forms of treatment.


Both lactulose and Amitiza (lubiprostone) have long-standing records of usage in patients with constipation, and are backed by numerous clinical studies indicating their effectiveness compared to placebo treatments. In some cases, these drugs may be combined under careful consideration by a physician due to potential interactions. They work differently: lactulose is an osmotic laxative that increases the amount of water in your bowels to stimulate bowel movements, while Amitiza enhances fluid secretion in your intestines promoting stool passage.

Lactulose is considered a first-line treatment option for chronic idiopathic constipation or opioid-induced constipation. On the other hand, Amitiza would usually be considered for adult women who suffer from irritable bowel syndrome with chronic idiopathic constipation or general population suffering from opioid-induced constipation.

Both medications are available as generic drugs which can save cost especially for patients paying out of pocket. The effects may not be noticeable right away; it might take few days before their action kicks in.

The side effect profiles between the two drugs vary somewhat but both are generally well-tolerated. Common side effects include bloating, gas and diarrhea with lactulose use; whereas nausea, diarrhea and headache might occur more frequently with Amitiza use. For both medications patients should seek medical help immediately if they experience severe abdominal pain or discomfort when starting treatment.