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Asacol HD

Generic name: mesalamine (oral) (me SAL a meen)
Brand name: Asacol HD
Drug class: 5-aminosalicylates

Medically reviewed by Sanjai Sinha, MD. Last updated on Apr 15, 2021.

What is Asacol HD?

Asacol HD (mesalamine) affects a substance in the body that causes inflammation, tissue damage, and diarrhea.

Asacol HD delayed-release 800mg tablets are used to treat moderately active ulcerative colitis in adults.

Warnings

Stop using Asacol HD 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 Asacol HD 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 Asacol HD 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. Asacol HD is not approved for use in anyone younger than 18 years old.

How should I take Asacol HD?

Take Asacol HD 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 Asacol HD.

Take Asacol HD on an empty stomach, at least 1 hour before or 2 hours after a meal.

Drink plenty of liquids to help prevent kidney stones.

Swallow the tablet whole and do not crush, chew, or break it. Tell your doctor if you have trouble swallowing the tablet.

Tell your doctor if you find undissolved tablets in your stool.

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 this medicine.

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:

800 mg delayed release tablets: 1600 mg orally 3 times a day
Duration of therapy: 6 weeks.

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 Asacol HD?

If you have a skin condition such as eczema, Asacol HD 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.

Asacol HD side effects

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

Stop using Asacol HD 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 Asacol HD 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 Asacol HD?

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.

Further information

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

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