Pentasa is a brand-name prescription drug that’s FDA-approved for use in adults with ulcerative colitis (UC).

UC is a type of inflammatory bowel disease. It causes swelling and ulcers (small sores) in the lining of your colon and rectum. UC is a chronic (long-term) condition, and your symptoms may change over time. You may have periods of flare-ups, when the disease is active (causing a lot of symptoms). And you may also have periods of remission, when your symptoms get better or go away.

Specifically, Pentasa is prescribed to:

  • induce remission of UC
  • treat mildly to moderately active UC

For more information about UC and how the drug is taken, see the “Pentasa Uses” and “How Pentasa works” sections below.

Drug details

Pentasa contains the active drug mesalamine and belongs to a class of drugs called aminosalicylates.

Pentasa comes as extended-release oral capsules that you’ll take several times per day. The drug’s extended-release coating helps make sure that Pentasa isn’t broken down until it reaches your colon. This ensures the drug works where it’s needed in your body.

Pentasa capsules come in two strengths: 250 milligrams (mg) and 500 mg.

Effectiveness

For information about the effectiveness of Pentasa, see the “Pentasa uses” section below.

Pentasa is available only as a brand-name medication. However, mesalamine, the active drug of Pentasa, is available as generic extended-release tablets. But it comes in different strengths than Pentasa.

A generic drug is an exact copy of the active drug in a brand-name medication. Generics usually cost less than brand-name drugs.

Pentasa can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking Pentasa. These lists do not include all possible side effects.

For more information about the possible side effects of Pentasa, talk with your doctor or pharmacist. They can give you tips on how to manage any side effects that may be concerning or bothersome.

Note: The Food and Drug Administration (FDA) tracks side effects of drugs it has approved. If you’d like to notify the FDA about a side effect you’ve had with Pentasa, you can do so through MedWatch.

Mild side effects

Mild side effects* of Pentasa can include:

Most of these side effects may go away within a few days or a couple of weeks. But if they become more severe or don’t go away, talk with your doctor or pharmacist.

* This is a partial list of mild side effects from Pentasa. To learn about other mild side effects, talk with your doctor or pharmacist, or view Pentasa’s prescribing information.
† For more information about this side effect, see “Side effect details” below.

Serious side effects

Serious side effects from Pentasa aren’t common, but they can occur. Call your doctor right away if you have serious side effects. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.

Serious side effects and their symptoms can include:

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

Side effect details

Here’s some detail on certain side effects this drug may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Pentasa.

Skin reactions

Severe skin reactions, such as Stevens-Johnson syndrome and toxic epidermal necrolysis, may occur while taking Pentasa. This side effect wasn’t reported in Pentasa’s clinical trials. However, there have been rare cases since the medication was approved for use.

Symptoms of skin reactions can include:

  • skin rash that may peel or blister
  • cough
  • body ache
  • fever

These reactions are rare, but they can be life threatening and may require treatment in a hospital. If you think you’re having a severe skin reaction, you should stop taking Pentasa and contact your doctor immediately. If your symptoms feel life threatening, seek emergency care right away by calling 911 or your local emergency number.

Your doctor will likely have you stop taking Pentasa if you have a severe skin reaction to the drug. They can discuss other treatment options for UC with you.

Hair loss

Some people taking Pentasa reported hair loss in clinical trials. But this was a rare side effect in the trials. It’s not known if Pentasa causes hair loss.

If you’re concerned about hair loss while taking Pentasa, talk with your doctor or pharmacist. Your pharmacist may recommend over-the-counter products to help with hair loss. Also, you can find more about hair loss treatments in this article.

Bloody diarrhea

Some people may experience bloody diarrhea while taking Pentasa. In clinical trials, this side effect was less common, while diarrhea without blood was more common.

Bloody diarrhea may be a symptom of UC, which Pentasa is taken to treat. However, it may also be a sign of a serious condition called mesalamine-induced acute intolerance syndrome. With this condition, your body is unable to tolerate mesalamine, the active drug of Pentasa.

Symptoms of mesalamine-induced acute intolerance syndrome can be similar to a UC flare-up. To learn more about these symptoms, see “Serious side effects” just above.

If you experience bloody diarrhea, or symptoms of mesalamine-induced acute intolerance syndrome, call your doctor right away. They’ll help you figure out what’s causing your symptoms. If you have mesalamine-induced acute intolerance syndrome, your doctor will likely recommend you stop taking Pentasa.

Allergic reaction

As with most drugs, some people can have an allergic reaction after taking Pentasa. Allergic reaction was reported when the drug became available for use. However, it isn’t known if Pentasa causes an allergic reaction for sure. This is because allergic reaction didn’t occur in clinical trials of the drug.

Symptoms of a mild allergic reaction can include:

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include:

  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your tongue, mouth, or throat
  • trouble breathing

Call your doctor right away if you have an allergic reaction to Pentasa, as the reaction could become severe. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.

The Pentasa dosage your doctor prescribes will depend on several factors. These include:

  • the type and severity of the condition you’re taking Pentasa to treat
  • your age
  • other medical conditions you may have

Typically, at the start of treatment, your doctor will recommend you take Pentasa several times per day. Your doctor will ultimately prescribe the smallest dosage that provides the desired effect.

The following information describes dosages that are commonly taken or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Drug forms

Pentasa comes as extended-release oral capsules. The drug’s extended-release coating helps make sure that Pentasa isn’t broken down until it reaches your colon. This ensures the drug works where it’s needed in your body.

Drug strengths (250 mg and 500 mg)

Pentasa capsules come in two strengths: 250 milligrams (mg) and 500 mg.

Dosage for treating ulcerative colitis

The usual dosage for treating ulcerative colitis (UC) is 4,000 mg per day. For this dosage, you’ll take two to four Pentasa capsules four times a day. Typically:

  • If you’re prescribed the 250 mg capsules, you’ll take four capsules per dose.
  • If you’re prescribed the 500 mg capsules, you’ll take two capsules per dose.

This is the typical starting dosage as well as the typical maintenance dosage. A maintenance dosage is the amount of drug you need to take long term to effectively treat your condition.

It’s best to take your doses at the same times each day, about 6 hours apart. You should continue taking the prescribed dose each day for as long as your doctor recommends.

To help make sure that you don’t miss a dose, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.

Will I need to take this drug long term?

Pentasa is meant to be taken as a long-term treatment. If you and your doctor determine that Pentasa is safe and effective for you, you’ll likely take it long term.

Other drugs are available that can treat your condition. Some may be a better fit for you than others. If you’re interested in finding an alternative to Pentasa, talk with your doctor. They can tell you about other medications that may work well for you.

Note: Some of the drugs listed here are used off-label to treat these specific conditions. Off-label drug use is when a drug that’s approved by the Food and Drug Administration (FDA) is prescribed for a purpose other than what it’s approved for.

Alternatives for treating ulcerative colitis

Examples of other drugs that may be taken to treat ulcerative colitis include:

As with all medications, the cost of Pentasa can vary. The actual price you’ll pay depends on your insurance plan, your location, and the pharmacy you use.

Keep in mind that you may be able to get a 90-day supply of Pentasa. If approved by your insurance company, getting a 90-day supply of the drug could reduce your number of trips to the pharmacy and help lower the cost. If you’re interested in this option, check with your doctor, pharmacist, or insurance company.

Before approving coverage for Pentasa, your insurance company may require you to get prior authorization. This means that your doctor and insurance company will need to communicate about your prescription before the insurance company will cover the drug. The insurance company will review the prior authorization request and decide if the drug will be covered.

If you’re not sure if you’ll need to get prior authorization for Pentasa, contact your insurance company.

Financial assistance

If you need financial support to pay for Pentasa, help may be available.

The Medicine Assistance Tool website lists programs that may help lower the cost of Pentasa. For more information and to find out if you’re eligible for support, visit this website.

To learn more about saving money on prescriptions, check out this article.

Mail-order pharmacies

Pentasa may be available through a mail-order pharmacy. Using this service may help lower the drug’s cost and allow you to get your medication without leaving home.

If recommended by your doctor, you may be able to receive a 90-day supply of Pentasa, so there’s less concern about running out of the medication. If you’re interested in this option, check with your doctor, pharmacist, or insurance company. Some Medicare plans may help cover the cost of mail-order medications.

If you don’t have insurance, you can ask your doctor or pharmacist about online pharmacy options.

Generic version

Pentasa is available only as a brand-name medication. However, mesalamine, the active drug of Pentasa, is available as a generic called mesalamine tablet extended-release. But it comes in different strengths than Pentasa.

A generic drug is an exact copy of the active drug in a brand-name medication. Generics usually cost less than brand-name drugs.

Here are answers to some frequently asked questions about Pentasa.

Is Pentasa an immunosuppressant?

No, Pentasa is not an immunosuppressant. An immunosuppressant is a drug that weakens your immune system. Instead, Pentasa belongs to a class of drugs called aminosalicylates.

Other drugs, including immunosuppressants and steroids, are prescribed to treat ulcerative colitis (UC). Similar to Pentasa, these drugs reduce inflammation (swelling) in your bowel. However, they work in a different way than Pentasa does. (For more information, see the “How Pentasa works” section below.)

Does Pentasa cause any long-term side effects?

It’s possible. Some long-term side effects have been reported during Pentasa treatment, including:

These side effects can occur at any time while taking Pentasa. They can even happen if you’ve been taking the drug for a long time without any problems.

If you’re concerned about side effects with Pentasa, talk with your doctor or pharmacist. To learn more, you can also see the “Pentasa side effects” section above.

Is Pentasa approved to treat Crohn’s disease?

No. Currently, the Food and Drug Administration (FDA) hasn’t approved Pentasa to treat Crohn’s disease. Pentasa is FDA-approved to treat UC. (For more information, see the “Pentasa uses” section below.)

Similar to UC, Crohn’s disease is a type of inflammatory bowel disease (IBD). Both conditions affect the lining of your bowel, but they can affect different parts of it. They can also cause different symptoms.

Pentasa may sometimes be prescribed off-label to treat Crohn’s disease. Off-label drug use is when an FDA-approved drug is prescribed for a purpose other than what it’s approved for.

If you have Crohn’s disease and want to learn about treatment options for your condition, talk with your doctor.

The Food and Drug Administration (FDA) approves prescription drugs such as Pentasa to treat certain conditions. Pentasa may also be used off-label for other conditions. Off-label drug use is when an FDA-approved drug is prescribed for a purpose other than what it’s approved for.

Pentasa for ulcerative colitis

Pentasa is FDA-approved to treat ulcerative colitis (UC) in adults. (See below for details about this condition.) Specifically, Pentasa is prescribed to:

  • Induce remission of UC. When UC is active, inflammation and ulcers in your bowel worsen. This causes your symptoms to flare up. When this happens, your doctor may prescribe Pentasa to treat these flare-ups until your symptoms go away. This is called inducing remission.
  • Treat mildly to moderately active UC. When UC is active and not in remission, you may have flare-ups of your symptoms. When this happens, your doctor may prescribe Pentasa to manage inflammation and reduce your symptoms.

About ulcerative colitis

UC is a type of inflammatory bowel disease. It’s a chronic (long-term) disease of inflammation (swelling) and ulcers (small sores) in the lining of your colon and rectum.

Symptoms of UC can include:

You can learn more about UC by visiting our MNT hub for inflammatory bowel disease (IBD).

Effectiveness for ulcerative colitis

Pentasa has been found to be effective in treating UC. Mesalamine, the active drug in Pentasa, is recommended as a treatment option for UC in the American Gastroenterological Association guidelines.

For more information on how the drug performed in clinical trials, see Pentasa’s prescribing information.

Pentasa and children

Pentasa isn’t approved for use in children. This drug has only been studied in adults. It’s not known if Pentasa is safe or effective in children.

If you’re interested in learning about UC treatments for your child, talk with their doctor.

Pentasa is prescribed to treat ulcerative colitis (UC) in adults. For more information about the drug’s uses, see the “Pentasa uses” section above.

What happens with ulcerative colitis

With UC, the lining of your colon and rectum become inflamed (swollen). This inflammation can cause ulcers (small sores) to develop in these linings. The inflammation can lead to symptoms such as diarrhea, fatigue, nausea, and weight loss. (To learn more about UC symptoms, see “Pentasa uses” above.)

UC is a chronic (long-term) condition. You may have periods of flare-ups, when the disease is active (causing a lot of symptoms). And you may also have periods of remission, when your symptoms get better or go away.

What Pentasa does

Pentasa contains the active drug mesalamine, also called 5-aminosalicylic acid. Mesalamine belongs to a drug class called aminosalicylates.

It’s not fully understood how mesalamine works to treat UC. But it’s thought that aminosalicylates work by lowering inflammation in the lining of your colon and rectum. This helps ulcers heal. They also manage UC flare-ups, which helps improve symptoms or induces remission.

When the disease is active, inflammation and ulcers in your bowel get worse, and your symptoms flare-up. When this happens, your doctor may prescribe Pentasa to induce remission by treating these flare-ups until your symptoms go away.

Once your condition is in remission, taking an aminosalicylate, such as Pentasa, helps manage the inflammation in your body. This helps prevent your UC symptoms from flaring up again.

How long does it take to work?

Pentasa starts working to manage inflammation in your bowel right away. However, it may take a few weeks before your symptoms improve.

Taking more than the recommended dosage of Pentasa can lead to serious side effects. Do not take more Pentasa than your doctor recommends.

Overdose symptoms

Symptoms of an overdose can include:

What to do in case of overdose

If you think you’ve taken too much of this drug, call your doctor. You can also call the American Association of Poison Control Centers at 800-222-1222 or use its online tool. But if your symptoms are severe, call 911 or your local emergency number, or go to the nearest emergency room right away.

There’s no known interaction between Pentasa and drinking alcohol. However, drinking alcohol may cause ulcerative colitis (UC) symptoms to flare up in some people. (Keep in mind that Pentasa is taken for UC.)

Also, if you get headaches or nausea from Pentasa, drinking alcohol could make these side effects worse. (For more information on side effects, see “Pentasa side effects” above.)

If you drink alcohol, talk with your doctor about how much, if any, is safe for you to drink while taking Pentasa.

Pentasa may interact with several other medications. The drug may also interaction with certain lab tests.

Different interactions can cause different effects. For instance, some interactions can interfere with how well a drug works. Other interactions can increase side effects or make them more severe.

Pentasa and other medications

Below is a list of medications that can interact with mesalamine, the active drug of Pentasa. This list does not contain all drugs that may interact with Pentasa.

Before taking Pentasa, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you take. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

  • Nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDs are pain-relieving drugs that reduce inflammation (swelling). Taking NSAIDs or drugs containing mesalamine can cause kidney problems.* So, taking an NSAID while you’re taking Pentasa may increase your risk of kidney problems. Examples of NSAIDs include:
  • Azathioprine or 6-mercaptopurine. Similar to Pentasa, these drugs are taken to treat ulcerative colitis. Taking these drugs with Pentasa may increase your risk of blood disorders and bone marrow failure. (With bone marrow failure, your body can’t make enough blood cells).

* For more information about side effects, see “Pentasa side effects” above.

Pentasa and herbs and supplements

There aren’t any herbs or supplements that have been specifically reported to interact with Pentasa. However, you should still check with your doctor or pharmacist before taking any of these products while taking Pentasa.

Pentasa and foods

There aren’t any foods that have been specifically reported to interact with Pentasa. If you have any questions about eating certain foods with Pentasa, talk with your doctor.

Pentasa and lab tests

Pentasa may interact with a certain lab test that’s used to check your normetanephrine level. (Normetanephrine is a substance that’s made when your body breaks down adrenaline.)

Before having any lab tests, be sure to tell your doctor that you’re taking Pentasa.

It’s not known if Pentasa is safe to take during pregnancy. Pentasa hasn’t been studied in pregnant people. However, there have been limited studies of mesalamine, the active drug in Pentasa, in pregnant people and in animals.

Although Pentasa hasn’t been studied in pregnant people, it’s important that ulcerative colitis (UC), which Pentasa is used for, is managed during pregnancy. If you’re pregnant and your UC is active (causing symptoms), studies suggest your risk of having a premature birth increases. Your child may also have a low birth weight.

Current American Gastroenterological Association (AGA) guidelines recommend people should avoid getting pregnant until their UC has been in remission for at least 3 months. (With remission, your symptoms get better or go away.) To help keep UC in remission, the AGA recommends doctors prescribe mesalamine during pregnancy. Current evidence suggests that the benefits of taking the drug to help keep UC in remission may outweigh the potential risks.

If you’re pregnant or planning a pregnancy, talk with your doctor about the risks and benefits of taking Pentasa during pregnancy.

It’s unknown if Pentasa is safe to take during pregnancy. If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs while you’re taking Pentasa.

For more information about taking Pentasa during pregnancy, see the “Pentasa and pregnancy” section above.

Pentasa may be safe to take while breastfeeding. Mesalamine, the active drug in Pentasa, is known to pass into breast milk in small amounts. And some children breastfed by people taking mesalamine have experienced diarrhea.

The current American Gastroenterological Association guidelines recommend people can breastfeed during mesalamine treatment if the child is monitored for diarrhea.

Talk with your doctor about the best way to feed your child while you’re taking Pentasa. If you decide to breastfeed while taking Pentasa, you should monitor your child for diarrhea.

You should take Pentasa according to the instructions your doctor gives you.

When to take

Typically, you’ll take your Pentasa dose four times per day. It’s best to space out your dosage evenly, once about every 6 hours. You should drink plenty of water when you take each Pentasa dose.

To help make sure that you don’t miss a dose, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.

Accessible labels and containers

If your prescription label is hard to read, talk with your doctor or pharmacist. Some pharmacies offer labels that have large print, braille, or a code you scan with a smartphone to convert text to speech. If your local pharmacy doesn’t have these options, your doctor or pharmacist may be able to direct you to one that does.

If you have trouble opening medication bottles, ask your pharmacist if they can put Pentasa in an easy-open container. They also may be able to recommend tools that can make it simpler to open lids.

Taking Pentasa with food

You can take Pentasa with or without food. Be sure to drink plenty of water when you take each Pentasa dose.

Can Pentasa be crushed, split, or chewed?

Pentasa capsules should be swallowed whole. Do not crush, split, or chew Pentasa capsules.

If you cannot swallow the whole capsule, you can open it and sprinkle its contents onto applesauce or yogurt. Be sure to take the applesauce or yogurt right away and avoid chewing it.

If you have problems taking Pentasa, talk with your doctor. You can also see this article.

This drug comes with several precautions. Before taking Pentasa, talk with your doctor about your health history. Pentasa may not be right for you if you have certain medical conditions or other factors affecting your health. These include:

  • An allergy to salicylate drugs. These drugs include aspirin, mesalamine (Apriso, Lialda), balsalazide (Colazal), olsalazine (Dipentum), and sulfasalazine (Azulfidine). Pentasa is an aminosalicylate, which is a certain type of salicylate. So, your doctor won’t prescribe the drug if you’ve ever had an allergic reaction to a salicylate medication.
  • Kidney problems. It’s possible for Pentasa to cause kidney problems and worsen kidney problems you already have. Before starting Pentasa treatment, your doctor will check your kidney function. They’ll also check it throughout your treatment. If any kidney problems develop or worsen, your doctor will recommend you stop taking Pentasa. Be sure to tell your doctor if you have a history of any kidney problems.
  • History of kidney stones. Some people taking Pentasa have reported kidney stones. If you have a history of kidney stones, talk with your doctor. They’ll help determine if another treatment option may be better for you. If you’re prescribed Pentasa, be sure to drink plenty of water to help reduce the risk of getting kidney stones.
  • Liver problems. Pentasa may cause liver problems and worsen any liver problems you already have. Your doctor may order blood tests to check how well your liver is working during your Pentasa treatment. If any liver problems develop or worsen, your doctor may recommend you stop taking Pentasa.
  • Heart problems. Rarely, mesalamine, the active drug in Pentasa, can cause heart problems. These include myocarditis (inflammation of the heart muscle) or pericarditis (inflammation of the lining of the heart). If you’ve ever had heart problems, talk with your doctor. They can advise if Pentasa is safe for you.
  • Skin conditions such as eczema or dermatitis. Pentasa may cause your skin to become more sensitive to the sun or ultraviolet light during treatment. And this may increase your risk of sunburn. If you already have skin conditions such as eczema or dermatitis, your skin may react more severely to Pentasa treatment. Talk with your doctor about what you can do to protect your skin while taking Pentasa.
  • Allergic reaction. If you’ve had an allergic reaction to Pentasa or any of its ingredients, your doctor will likely recommend that you don’t take Pentasa. Ask your doctor what other medications are better options for you.
  • Pregnancy. It’s unknown if Pentasa is safe to take during pregnancy. For more information, see the “Pentasa and pregnancy” section above.
  • Breastfeeding. Pentasa may be safe to take while breastfeeding. To learn more, see the “Pentasa and breastfeeding” section above.

Note: For more information about the potential negative effects of Pentasa, see the “Pentasa side effects” section above.

When you get Pentasa from the pharmacy, the pharmacist will add an expiration date to the label on the bottle. This date is typically 1 year from the date they dispensed the medication.

The expiration date helps guarantee that the medication is effective during this time. The current stance of the Food and Drug Administration (FDA) is to avoid taking expired medications. If you have unused medication that’s gone past the expiration date, talk with your pharmacist about whether you might still be able to take it.

Storage

How long a medication remains good to take can depend on many factors, including how and where you store the medication.

Pentasa capsules should be stored at room temperature (around 77˚F or 25˚C) in a tightly sealed container. Avoid storing this medication in areas where it could get damp or wet, such as bathrooms.

Disposal

If you no longer need to take Pentasa and have leftover medication, it’s important to dispose of it safely. This helps prevent others, including children and pets, from taking the drug by accident. It also helps keep the drug from harming the environment.

This article provides several useful tips on medication disposal. You can also ask your pharmacist for information about how to dispose of your medication.

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.