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Pentasa

Generic name: mesalamine (oral) [ me-SAL-a-meen ]
Drug class: 5-aminosalicylates

Medically reviewed by Sophia Entringer, PharmD. Last updated on Apr 16, 2021.

What is Pentasa?

Pentasa affects a substance in the body that causes inflammation, tissue damage, and diarrhea.

Pentasa is used to treat mild to moderate ulcerative colitis in adults. Ucerative colitis is associated with inflammation, ulcers and sores in the bowel causing bleeding, stomach pain, and diarrhoea.

Pentasa is also used off-label in the USA as a treatment for Crohn’s disease. Use of Pentasa to treat Crohn’s disease is officially approved in some other countries.

Warnings

Stop using Pentasa and call your doctor at once if you have severe stomach pain, stomach cramping, bloody diarrhea (may occur with fever, headache, and skin rash).

Before taking this medicine

You should not use Pentasa if you are allergic to mesalamine, aspirin, sulfasalazine, or salicylates (such as Disalcid, Doans Pills, Dolobid, Kaopectate, Nuprin Backache, Pepto-Bismol, Tricosal, Trilisate, and others).

To make sure Pentasa is safe for you, tell your doctor if you have ever had:

  • a kidney stone or kidney disease;

  • liver disease;

  • a blockage in your stomach or intestines (such as pyloric stenosis); or

  • a skin condition such as eczema.

Tell your doctor if you are pregnant or plan to become pregnant. It is not known whether mesalamine will harm an unborn baby. However, having untreated or uncontrolled ulcerative colitis during pregnancy may cause complications such as low birth weight or premature birth. The benefit of treating ulcerative colitis may outweigh any risks to the baby.

It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk. If you are breastfeeding, tell your doctor if you notice diarrhea in the nursing baby.

Do not give this medicine to a child without medical advice.

How should I take Pentasa?

Take Pentasa exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

This medicine can affect the results of certain medical tests. Tell any doctor who treats you that you are using mesalamine.

Drink plenty of liquids to help prevent kidney stones.

Pentasa can be taken with or without food.

Swallow the capsule whole and do not chew or crush the contents of the capsule. Tell your doctor if you have trouble swallowing the capsule.

If you cannot swallow a Pentasa capsule whole, open it and sprinkle the medicine into a spoonful of yogurt or applesauce. Swallow all of the mixture immediately without chewing. Do not save it for later use.

Call your doctor if your ulcerative colitis symptoms do not improve, or if they get worse.

This medicine can affect the results of certain medical tests. Tell any doctor who treats you that you are using mesalamine.

You may need frequent blood tests to check your blood cells or kidney function.

Store at room temperature away from moisture and heat.

Dosing information

Usual Adult Dose for Ulcerative Colitis -- Active:

250 and 500 mg extended-release capsules: 1 g orally 4 times a day
Duration of therapy: Up to 8 weeks.

Uses: Treatment of mildly to moderately active ulcerative colitis and induction of remission of ulcerative colitis.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Pentasa?

If you have a skin condition such as eczema, mesalamine could make you sunburn more easily. Avoid sunlight or tanning beds. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Pentasa side effects

Get emergency medical help if you have signs of an allergic reaction to Pentasa: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using Pentasa and call your doctor at once if you have:

  • severe stomach pain, stomach cramping, bloody diarrhea;

  • fever, headache, general ill feeling;

  • rash, itching, eye redness;

  • bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds;

  • low white blood cell counts - fever, chills, mouth sores, skin sores, sore throat, cough, feeling light-headed, trouble breathing;

  • signs of a kidney stone - severe pain in your side and back, frequent need to urinate, foul-smelling urine, dark or cloudy urine;

  • kidney problems - increased or decreased urination, swelling, weight gain; or

  • liver problems - loss of appetite, upper stomach pain, tiredness, easy bruising or bleeding, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Low white blood cell counts may be more likely in older adults.

Common Pentasa side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Pentasa?

Mesalamine can harm your kidneys, especially if you also use certain medicines for infections, cancer, osteoporosis, organ transplant rejection, bowel disorders, high blood pressure, or pain or arthritis (including Advil, Motrin, and Aleve).

Tell your doctor about all your other medicines, especially:

This list is not complete. Other drugs may interact with mesalamine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Popular FAQ

How long does it take for mesalamine to work?

Research studies looking at patients who received daily oral doses of 4 to 6 grams of mesalamine showed that 80% of patients achieved complete or significant clinical improvement within 4 weeks.

When is the best time to take mesalamine?

The best time to take or use mesalamine will depend on the specific product you are using and why you are using it (ulcerative colitis induction or maintenance, ulcerative proctitis). Some products may need to be taken with food while others are taken on an empty stomach. Check with your doctor.

How long can you take mesalamine?

Some forms of mesalamine are used long-term as a maintenance therapy in ulcerative colitis to help prevent symptoms from flaring up. Not all forms or brands of mesalamine are used long-term, so check with your doctor about your specific medicine. Call your doctor if your ulcerative colitis symptoms get worse after starting treatment.

What is the maximum dosage of mesalamine?

Mesalamine is available as delayed-release tablets or capsules, extended-release capsules, and rectal preparations like suppositories or enemas. The maximum dose will depend upon the specific product you are using and your diagnosis. Only use the dose prescribed by your doctor.

Why is mesalamine so expensive?

Brand name products of mesalamine may be more expensive than generic options. Some, but not all mesalamine products are available as generics. Your insurance should help pay for generics, or if you are paying out-of-pocket, ask your healthcare provider if there is a more affordable option.

Is mesalamine an immunosuppressant?

Mesalamine is an antiinflammatory, not an immunosuppressant. It may be one of the first treatments used for ulcerative colitis (UC) to lessen symptoms like diarrhea, rectal bleeding, or stomach pain. Immunosuppression is not a listed side effect for mesalamine. Other medicines used for UC, like prednisone, can suppress the immune system.

Can I stop taking mesalamine?

Mesalamine is used in some patients with ulcerative colitis as a maintenance (long-term) treatment to help you stay in remission (without active symptoms). Other treatments for ulcerative colitis or proctitis are only taken short-term. Ask your doctor when you can stop taking treatment.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Pentasa only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.