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URL of this page: https://medlineplus.gov/druginfo/meds/a614021.html

Mesalamine Rectal

pronounced as (me sal' a meen)

Why is this medication prescribed?

Rectal mesalamine is used to treat ulcerative colitis (a condition which causes swelling and sores in the lining of the colon [large intestine] and rectum), proctitis (swelling in the rectum), and proctosigmoiditis (swelling in the rectum and sigmoid colon [last section of the colon]). Rectal mesalamine is in a class of medications called anti-inflammatory agents. It works by stopping the body from producing a certain substance that may cause inflammation.

How should this medicine be used?

Rectal mesalamine comes as a suppository and an enema to use in the rectum. The suppository and the enema are usually used once a day at bedtime. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use rectal mesalamine exactly as directed. Do not use it more or less of it or use it more often than prescribed by your doctor.

You should begin to feel better during the first few days or weeks of your treatment with rectal mesalamine. Continue to use rectal mesalamine until you finish your prescription, even if you feel better at the beginning of your treatment. Do not stop using rectal mesalamine without talking to your doctor.

Mesalamine suppositories and enemas may stain clothing and other fabrics, flooring, and painted, marble, granite, enamel, vinyl, and other surfaces. Take precautions to prevent staining when you use these medications.

Drink plenty of fluids while using mesalamine suppositories and enemas.

If using a mesalamine enema, follow these steps:

  1. Try to have a bowel movement. The medication will work best if your bowels are empty.
  2. Use scissors to cut the seal of the protective foil pouch that holds seven bottles of medication. Be careful not to squeeze or cut the bottles. Remove one bottle from the pouch.
  3. Look at the liquid inside the bottle. It should be off-white or tan colored. The liquid may darken slightly if the bottles are left out of the foil pouch for a time. You may use liquid that has darkened a little bit, but do not use liquid that is dark brown.
  4. Shake the bottle well to make sure the medication is mixed.
  5. Remove the protective cover from the applicator tip. Be careful to hold the bottle by the neck so that the medication will not leak out of the bottle.
  6. Lie on your left side with your lower (left) leg straight and your right leg bent toward your chest for balance. You can also kneel on a bed, resting your upper chest and one arm on the bed.
  7. Gently insert the applicator tip into your rectum, pointing it slightly toward your navel (belly button).
  8. Hold the bottle firmly and tilt it slightly so that the nozzle is aimed toward your back. Squeeze the bottle slowly and steadily to release the medicine.
  9. Withdraw the applicator. Remain in the same position for at least 30 minutes to allow the medicine to spread through your intestine. Try to keep the medicine inside of your body for about 8 hours (while you sleep).
  10. Dispose of the bottle safely, so that is out of the reach of children and pets. Each bottle contains only one dose and should not be reused.

If using a mesalamine suppository, follow these steps:

  1. Try to have a bowel movement just before using the suppository. The medication will work best if your bowels are empty.
  2. Separate one suppository from the strip of suppositories. Hold the suppository upright and use your fingers to peel off the plastic wrapper. Try to handle the suppository as little as possible to avoid melting it with the heat of your hands.
  3. Lie down on your left side and raise your right knee to your chest. (If you are left-handed, lie on your right side and raise your left knee.)
  4. Using your finger, insert the suppository into the rectum, pointed end first. Use gentle pressure to insert the suppository completely. Try to keep it in place for 1 to 3 hours or longer if possible.
  5. Wash your hands thoroughly before you resume your normal activities.

If you will be using mesalamine enemas or suppositories, ask your pharmacist or doctor for a copy of the manufacturer's information for the patient that comes with the medication.

Other uses for this medicine

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before using mesalamine,

  • tell your doctor and pharmacist if you are allergic to mesalamine, salicylate pain relievers such as aspirin, diflunisal, magnesium salicylate (Doan's, others); sulfasalazine (Azulfidine); any other medications; or to any of the ingredients found in mesalamine enemas or suppositories. Tell your doctor if you are allergic to sulfites (substances used as food preservatives and found naturally in some foods) or any foods, dyes, or preservatives. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.Your doctor may need to change the doses of your medications or monitor you more carefully for side effects.
  • tell your doctor if you have or have ever had myocarditis (swelling of the heart muscle), pericarditis (swelling of the sac around the heart), asthma, allergies, or liver or kidney disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while using rectal mesalamine, call your doctor.
  • plan to avoid unnecessary or prolonged exposure to the sunlight and to wear protective clothing, sunglasses, and sunscreen. Mesalamine may make your skin sensitive to sunlight.
  • you should know that mesalamine may cause a serious reaction. Many of the symptoms of this reaction are similar to the symptoms of ulcerative colitis, so it may be difficult to tell if you are experiencing a reaction to the medication or a flare (episode of symptoms) of your disease. Call your doctor if you experience some or all of the following symptoms: stomach pain or cramping, bloody diarrhea, fever, headache, weakness, or rash.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Use the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not use a double dose to make up for a missed one.

What side effects can this medication cause?

Rectal mesalamine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • leg, back, or joint pain
  • heartburn
  • gas
  • dizziness
  • hemorrhoids
  • acne
  • pain in the rectum
  • hair loss

Some side effects can be serious. If you experience any of the following symptoms or those listed in the SPECIAL PRECAUTIONS section, call your doctor immediately:

  • rash, hives, itching, or peeling or blistering skin
  • mouth sores or blisters
  • swelling of the eyes, face, lips, tongue, mouth, or throat
  • fever or flu-like symptoms
  • swollen glands
  • red, itchy, irritated, or watery eyes
  • chest pain
  • shortness of breath
  • side or back pain
  • decreased urination
  • swelling of the legs, ankles, or feet
  • difficult or painful urination, pink or red colored urine, or blood in urine
  • extreme tiredness
  • yellowing of the skin or eyes
  • pain in the right upper part of the stomach
  • pale stools

Mesalamine may cause other side effects. Call your doctor if you have any unusual problems while you are using this medication.

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light, excess heat and moisture (not in the bathroom). You may store mesalamine suppositories in the refrigerator. Once you open the foil package of mesalamine enemas use all the bottles promptly, as directed by your doctor.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (https://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

  • nausea
  • vomiting
  • abdominal pain
  • fast or shallow breathing
  • ringing in the ears
  • headache
  • dizziness
  • confusion
  • seizures

What other information should I know?

Keep all appointments with your doctor and the laboratory.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are using mesalamine.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Canasa®
  • Rowasa®
  • sfRowasa®

Other names

  • 5-ASA
  • mesalazine
Last Revised - 01/15/2023