Linzess (linaclotide) is a brand-name oral capsule that’s prescribed for certain digestive system issues, including some types of constipation. As with other drugs, Linzess can cause side effects, such as gas, diarrhea, and headache.

To learn more about the uses of Linzess, see this article.

Linzess can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Linzess in clinical trials:

* For more information about this side effect, see “Side effect specifics” below.

Mild side effects can occur with Linzess use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to the prescribing information for Linzess.

Mild side effects that have been reported with Linzess include:

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you develop a side effect while taking Linzess and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.

Linzess may cause serious side effects. Though serious side effects aren’t common, they can occur. The list below may not include all possible serious side effects of the drug. For further details, you can refer to the prescribing information for Linzess.

If you develop serious side effects while taking Linzess, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Serious side effects that have been reported and their symptoms include:

* Linzess has a boxed warning for this side effect. This is a serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effect specifics” section below.
† For more information about this side effect, see “Side effect specifics” below.

Linzess is approved to treat functional constipation in children ages 6 years and older. (Functional constipation occurs in childhood and has no clear medical cause.) In clinical trials of Linzess for this condition, the most common side effect children experienced was diarrhea. Nausea, dehydration, and abdominal discomfort were also reported in these trials.

In addition, Linzess has a boxed warning about the risk of serious dehydration in children younger than age 2 years. This is a serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about drug effects that may be dangerous. For more information, see the section below called “Side effect specifics.”

Linzess may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

Can Linzess cause weight gain or weight loss as a side effect?

You shouldn’t experience weight gain or weight loss from taking Linzess. Weight changes weren’t reported in clinical trials of people taking the drug.

However, Linzess works to treat constipation in certain people. Constipation may cause bloating, which can lead to weight gain. So, in some cases, treating constipation may cause weight loss.

In addition, Linzess can cause diarrhea as a side effect. If diarrhea is severe, it’s possible for weight loss to occur.

If you notice weight changes during your treatment with Linzess, talk with your doctor. They can determine what may be causing your weight change to occur and the best ways to manage your weight.

What are the long-term side effects of Linzess?

Linzess hasn’t been reported to cause long-term side effects at this time. Side effects that people taking Linzess reported in clinical trials only occurred during treatment with Linzess.

Your body may adjust to the side effects of Linzess over time so that you experience fewer side effects during your treatment. In addition, when people stop treatment with Linzess, side effects should stop as well.

If you have questions or concerns about long-term side effects from taking Linzess, talk with your doctor.

Is fatigue a side effect of Linzess?

No, you shouldn’t experience fatigue from taking Linzess. This wasn’t a side effect reported in clinical trials of Linzess.

However, it’s possible to develop fatigue from severe diarrhea, especially if you become dehydrated. If you’re feeling more tired than usual during your treatment with Linzess, talk with your doctor. They can determine what may be causing your fatigue and the best ways to manage it.

Is Linzess prescribed for digestive conditions, such as constipation?

Linzess is currently approved to treat irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC) in adults. Doctors also prescribe it to treat functional constipation (FC) in children ages 6 years and older. (FC occurs in childhood and has no clear medical cause.)

At this time, Linzess isn’t approved to treat other causes of constipation or conditions associated with constipation besides IBS-C. If you’re experiencing long-term constipation, talk with your doctor. They can determine the type of constipation you have and then recommend the best treatment options for your condition.

If you have temporary constipation, your doctor may be able to recommend an over-the-counter treatment for you, such as MiraLAX (polyethylene glycol). However, if your condition is long term, they may recommend a prescription for constipation.

If you’d like to learn more about Linzess, talk with your doctor. You can also visit the manufacturer’s website to find Linzess reviews for constipation. However, the best way to determine whether Linzess may be a good treatment option for you is by talking with your doctor.

Does Linzess cause hair loss as a side effect?

No, you shouldn’t experience hair loss from taking Linzess. Hair loss wasn’t a side effect that people taking the drug reported in clinical trials.

In some cases, antidepressant drugs such as Zoloft (sertraline) or Lexapro (escitalopram) may be used off-label to treat IBS-C. Off-label use of a drug is when your doctor prescribes the drug for a different use than what the Food and Drug Administration (FDA) approved it for. Although Zoloft and Lexapro are most often used to treat depression, your doctor may also recommend them for other uses, such as IBS-C. And it’s possible for these drugs to increase your risk of hair loss occurring.

If you experience hair loss during treatment with Linzess, talk with your doctor. They can determine what may be causing your hair loss and the best ways to manage it.

Do side effects of 72-mcg, 145-mcg, and 290-mcg Linzess capsules differ?

It’s possible for side effects to differ based on the dose of Linzess you take. So people taking a higher dose of the drug may be at an increased risk of side effects occurring from Linzess.

For example, if you take a dose of 290 micrograms (mcg) of Linzess, you may have a higher risk of side effects occurring compared with someone taking a dose of 72 mcg. This is because when your body is exposed to more of a drug, your risk of side effects is higher.

If you have concerns about side effects occurring from Linzess, talk with your doctor about the best dose for you.

Learn more about some of the side effects of Linzess. To find out how often side effects occurred in clinical trials, see the prescribing information for Linzess.

Risk of serious dehydration in children younger than age 2 years

Linzess has a boxed warning about risk of serious dehydration in children younger than age 2 years. This is a serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about the risks of taking a medication.

At this time, Linzess is not approved for use in children younger than 6 years of age. (Doctors may prescribe Linzess to treat functional constipation in children ages 6 years and older.)

In animal studies, young animals had severe diarrhea that led to dehydration. In some cases, this was even life threatening. Because of this possible risk, doctors typically won’t prescribe Linzess to children younger than age 2 years.

It’s important to note that Linzess wasn’t studied in children under age 2 years. And since animal studies don’t always indicate what may happen in humans, it’s not known exactly how the drug may work in children younger than 6 years of age.

If your child is prescribed Linzess, you should monitor them for symptoms of dehydration during treatment. Symptoms of mild dehydration include:

  • thirst
  • dark-colored urine
  • headache
  • weakness

Symptoms of severe dehydration include:

What you can do

If your child is taking Linzess, try to help them stay hydrated during treatment. For tips on staying hydrated and rehydrating, refer to this article. Your child’s doctor can also give you advice on how to prevent your child from becoming dehydrated.

If your child experiences symptoms of dehydration during Linzess treatment, contact their doctor. If the symptoms are severe, call 911 or take your child to the nearest emergency room right away.

Headache

It’s possible to experience headache from taking Linzess. Though this wasn’t one of the most common side effects of the drug, it was reported in clinical trials of Linzess for irritable bowel syndrome with constipation (IBS-C) in adults. This side effect wasn’t reported in clinical trials of adults taking Linzess for chronic idiopathic constipation (CIC) or children taking the drug for functional constipation (FC).

What you can do

If you experience headache from taking Linzess, talk with your doctor. They can recommend the best ways to manage your headaches. In some cases, they may recommend taking an over-the-counter drug such as Tylenol (acetaminophen).

It’s important to note that headache may also be a symptom of dehydration, which can occur if you develop severe diarrhea with Linzess. Your doctor can determine what may be causing your headaches and the best treatment option for you.

Diarrhea

You may develop diarrhea during treatment with Linzess. In fact, diarrhea was the most common side effect that people taking Linzess reported in clinical trials. People taking the drug for IBS-C, CIC, or FC reported diarrhea as the most common side effect.

In the trials, diarrhea most often began within the first 2 weeks of starting Linzess. This was also the most common reason that people stopped treatment with Linzess.

In most cases, diarrhea was mild in the trials. However, it’s possible to develop severe diarrhea from this drug. Symptoms of severe diarrhea may include:

What you can do

Tell your doctor if you experience diarrhea while taking Linzess. They can determine whether it’s mild or severe and let you know the best treatment options.

If you do develop severe diarrhea, your doctor will likely recommend that you stop taking Linzess temporarily to treat your diarrhea. They will also recommend hydrating so you don’t become dehydrated from the severe diarrhea.

Gas

It’s possible to experience gas while taking Linzess. Gas was one of the more common side effects that people taking Linzess reported in clinical trials. Symptoms of gas may include abdominal cramping or bloating.

What you can do

If you notice gas that’s bothersome to you while taking Linzess, talk with your doctor or pharmacist. In some cases, they may be able to recommend an over-the-counter treatment such as Gas-X (simethicone).

Allergic reaction

As with most drugs, Linzess can cause an allergic reaction in some people.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, such as a rash, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep taking Linzess. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Before starting treatment with Linzess, tell your doctor about any medical conditions that you have. This can help them determine whether Linzess is a safe treatment option for you.

Boxed warning: Risk of serious dehydration in children younger than age 2 years

This drug has a boxed warning for risk of serious dehydration in children younger than age 2 years. This is a serious warning from the Food and Drug Administration (FDA). For details, see the “Side effect specifics” section above.

Other precautions

Be sure to talk with your doctor about your health history before you take Linzess. This drug may not be the right treatment for you if you have certain medical conditions that affect your health. These are considered drug-condition interactions. The conditions to consider include:

Intestinal blockage: If you have an intestinal blockage, your doctor will likely recommend a different treatment option for you. Linzess works by moving your food through your intestines quicker than usual. And if you have an intestinal obstruction, taking Linzess may make your condition worse. In this case, your doctor can help determine the best treatment plan for you.

Allergic reaction: If you’ve had an allergic reaction to Linzess or any of its ingredients, your doctor will likely not prescribe Linzess. Ask your doctor what other medications may be better options for you.

Alcohol with Linzess

Linzess isn’t known to interact with alcohol. However, drinking alcohol can make certain side effects of Linzess worse. For example, both Linzess and alcohol can cause headaches. So you may be at an increased risk of headaches occurring if you take Linzess and drink alcohol.

In addition, Linzess can cause severe diarrhea, which may lead to dehydration. Alcohol can also increase your risk of dehydration.

If you’d like to drink alcohol during your treatment with Linzess, talk with your doctor. They can let you know what amount of alcohol, if any, is safe to drink while taking Linzess.

Pregnancy and breastfeeding while taking Linzess

It’s not known whether it’s safe to take Linzess during pregnancy or while breastfeeding.

Linzess works in your intestines, and only a small amount is likely absorbed into your body. So a developing fetus would likely be exposed to only a small amount of the medication. However, there haven’t been enough clinical trials done during pregnancy to determine whether the drug may increase the risk of congenital anomalies (also known as birth defects).

Most studies in pregnant animals did not show an increased risk of congenital anomalies. But studies in which animals were exposed to large amounts of Linzess did show an increased risk of congenital anomalies. However, it’s important to note that animal studies don’t always indicate what may happen in humans.

In addition, Linzess isn’t believed to pass into breast milk. So a child who is breastfed by someone taking Linzess may not be exposed to the drug. However, it’s not known whether Linzess may affect the production of breast milk.

If you’re pregnant or breastfeeding, or planning to become pregnant or breastfeed, talk with your doctor before taking Linzess. They can determine whether Linzess is right for you.

In most cases, side effects of Linzess are mild. But it’s possible to develop severe side effects from this drug as well.

If you’d like to learn more about Linzess, talk with your doctor or pharmacist. They can help answer any questions you have about side effects from taking the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.