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Treatments > Medications Used In MS

Brand Name Chemical Name

Metamucil (available in granule form in Canada, in wafer form in the U.S., and in powder or effervescent powder in the U.S. and Canada) is one of several available brands of bulk-forming laxative.

Psyllium hydrophilic mucilloid (sill-i-yum hye-droe-fill-ik myoo-sill-oid)

Primary Usage in MS

Generic Available
Constipation No
This medication is available without a prescription.

Psyllium hydrophilic mucilloid is a bulk-forming oral laxative. This type of laxative is not digested by the body; it absorbs liquids from the intestines and swells to form a soft, bulky stool. The bowel is then stimulated normally by the presence of the bulky stool.

Proper Usage
Laxatives are to be used to provide short-term relief only, unless otherwise directed by the nurse or physician who is helping you to manage your bowel symptoms. A regimen that includes a healthy diet containing roughage (whole grain breads and cereals, bran, fruit, and green, leafy vegetables), six to eight full glasses of liquids each day, and some form of daily exercise is most important in stimulating healthy bowel function.

If your physician has recommended this laxative for management of constipation, follow his or her recommendations for its use. If you are treating yourself for constipation, follow the directions on the package insert. Results are often obtained in twelve hours but may take as long as two or three days. Be sure to consult your physician if you experience problems or do not get relief within a week.

In order for this type of bulk-forming laxative to work effectively without causing intestinal blockage, it is advisable to drink six to eight glasses (eight ounces) of water each day. Each dose of the laxative should be taken with eight ounces of cold water or fruit juice. If concerns about loss of bladder control keep you from drinking this amount of water, discuss it with the nurse or physician who is helping you manage your bowel and bladder symptoms.

Do not take any type of laxative if you have signs of appendicitis or inflamed bowel (e.g., stomach or lower abdominal pain, cramping, bloating, soreness, nausea, or vomiting). Check with your physician as soon as possible.

Do not take any laxative for more than one week unless you have been told to do so by your physician. Many people tend to overuse laxatives, which often leads to dependence on the laxative action to produce a bowel movement. Discuss the use of laxatives with your health care professional in order to ensure that the laxative is used effectively as part of a comprehensive, healthy bowel management regimen.

Do not take any laxative within two hours of taking another medication because the desired effectiveness of the other medication may be reduced.

Bulk-forming laxatives are commonly used during pregnancy. Some of them contain a large amount of sodium or sugars, which may have possible unwanted effects such as increasing blood pressure or causing fluid retention. Look for those that contain lower sodium and sugar.

Some laxatives pass into breast milk. Although it is unlikely to cause problems for a nursing infant, be sure to let your physician know if you are using a laxative and breastfeeding at the same time.

Possible Side Effects
Check with your physician as soon as possible if you experience any of the following: difficulty breathing; intestinal blockage; skin rash or itching; swallowing difficulty (feelings of lump in the throat).

Medication Index

Other Medications Used to Treat Constipation

About Bowel Dysfunction

Bowel Problems: The Basic Facts
Types of bowel problems, good bowel habits, resources, and more.

Reprinted with permission from Rosalind C. Kalb (ed.), Multiple Sclerosis: The Questions You Have—The Answers You Need, 3rd Edition. New York: Demos Medical Publishing, Inc., 2004

Last updated December 21, 2004