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Canasa Pac (rectal)

Generic name: mesalamine (rectal) [ me-SAL-a-meen ]
Brand names: Canasa, Rowasa, sfRowasa, Canasa Pac rectal
Drug class: 5-aminosalicylates

Medically reviewed by Drugs.com on Aug 14, 2023. Written by Cerner Multum.

What is Canasa Pac rectal?

Canasa Pac is used to treat ulcerative colitis, proctitis, and proctosigmoiditis in adults.

Canasa Pac may also be used for purposes not listed in this medication guide.

Canasa Pac rectal side effects

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

Canasa Pac may cause serious side effects. Stop using Canasa Pac and call your doctor at once if you have:

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

Common side effects of Canasa Pac 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.

Canasa Pac side effects (more detail)

Warnings

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

Before taking this medicine

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

Tell your doctor if you have ever had:

If you are breastfeeding, tell your doctor if you notice diarrhea in the nursing baby.

How should I use Canasa Pac rectal?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Do not take a rectal suppository or enema by mouth. Use it only in your rectum.

For best results, use Canasa Pac at bedtime. Try to empty your bowel and bladder before using rectal medicine. Read and carefully follow any Instructions for Use provided with your medicine.

Wash your hands before and after using rectal medicine.

Remove the wrapper before inserting the suppository. Avoid handling the suppository too long or it will melt. Lie on your back with your knees up toward your chest. Gently insert the suppository into your rectum about 1 inch, pointed tip first.

Stay lying down for a few minutes while the suppository melts. You should feel little or no discomfort. Avoid using the bathroom for 1 to 3 hours or longer, if possible.

Shake the rectal enema liquid well just before each use.

Drink plenty of liquids while you are using Canasa Pac.

To use the enema, lie on your left side with your left leg extended and your right leg slightly bent. Remove the cap from the applicator tip and gently insert the tip into your rectum. Slowly squeeze the bottle to empty the contents into the rectum.

After using the enema, lie down on your left side for at least 30 minutes to allow the liquid to distribute throughout your intestines. Avoid using the bathroom, and hold in the enema at least 8 hours, or all night, if possible.

Drink plenty of water each day.

It may take up to 3 weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve.

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

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

Store at cool room temperature away from moisture and heat.

The enema liquid may darken in color after it has been removed from the foil pouch. This should not affect the medicine. However, throw away any enema liquid that has turned dark brown.

Detailed Canasa Pac dosage information

hydrocortisone, mesalamine, Lialda, Pentasa, Cortef, Asacol

What happens if I miss a dose?

Skip the missed dose and wait until your next bedtime to use the medicine. Do not use 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 using Canasa Pac rectal?

Avoid getting Canasa Pac on clothing, flooring, painted surfaces, vinyl, marble, granite, and other surfaces. Canasa Pac products may stain surfaces.

If you have a skin condition such as eczema, Canasa Pac 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.

What other drugs will affect Canasa Pac rectal?

Canasa Pac 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 affect Canasa Pac, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Canasa Pac drug interactions (more detail)

Does Canasa Pac interact with my other drugs?

Enter medications to view a detailed interaction report using our Drug Interaction Checker.

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.

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.

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.

What are 7 mesalamine side effects to be aware of?

Common side effects of mesalamine include stomach problems (such as burping, abdominal pain, constipation, and diarrhea); a headache or dizziness; nasal problems, such as nasal congestion, runny nose, sneezing, or itching; or a rash. For most people, these side effects lessen or go away after a few weeks of treatment. More serious side effects with mesalamine are less common or rare, but include allergic reactions, bloody diarrhea or blood in the urine, and an intolerance syndrome. Continue reading

Further information

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

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

Medical Disclaimer

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