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Canasa Pac (rectal)

Generic Name: mesalamine (rectal) (me SAL a meen)
Brand Name: Canasa, Canasa Pac, Rowasa, sfRowasa

Medically reviewed on Sep 11, 2017

What is Canasa Pac rectal?

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

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

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

Important Information

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 it.

To make sure Canasa Pac is safe for you, tell your doctor if you have:

It is not known whether Canasa Pac will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether mesalamine passes into breast milk or if it could affect the nursing baby. Tell your doctor if you are breast-feeding.

How should I use Canasa Pac rectal?

Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Do not take rectal medicine by mouth. It is for use only in your rectum.

For best results, use Canasa Pac at bedtime. Try to empty your bowel and bladder just before using the medicine.

Wash your hands before and after inserting the rectal suppository.

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

For best results, stay lying down for a few minutes. The suppository will melt quickly and you should feel little or no discomfort while holding it in. Avoid using the bathroom for at least an hour after using the suppository.

Shake the rectal enema liquid well just before each use.

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.

For best results, try to hold in the enema for at least 30 minutes, or all night if possible, to allow the liquid to distribute throughout your intestines. Avoid using the bathroom during this time.

Read all patient information, medication guides, and instruction sheets provided to you. Ask your doctor or pharmacist if you have any questions.

Store at cool room temperature away from moisture and heat.

The rectal 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.

What happens if I miss a dose?

Skip the missed dose and wait until your next bedtime to use the medicine. Do not use extra medicine to make up the missed dose.

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 the rectal suppositories or enema liquid on clothing, flooring, painted surfaces, vinyl, marble, granite, and other surfaces. Canasa Pac products may stain surfaces.

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.

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

Common side effects may include:

  • stomach pain, nausea, gas;

  • fever, cold or flu symptoms;

  • rash; or

  • feeling tired.

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 Canasa Pac rectal?

Other drugs may interact with mesalamine, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

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.