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Orlistat (Oral-Local)

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Orlistat (Oral-Local)

US Brand Names

• Xenical


Orlistat (OR-li-stat) is used as an aid to help you lose weight. The medicine prevents the digestion of some of the fat you eat. Fats that are not digested cannot be absorbed and therefore do not contribute calories. To give the greatest weight loss, orlistat must be used with a weight-reduction diet.

Orlistat is available only with your doctor's prescription, in the following dosage form(s):


    • Capsules (U.S.)

Special Considerations

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For orlistat, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to orlistat. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.


When using orlistat, your diet should contain no more than 30% of calories as fat. More fat in your diet will increase the side effects of this medicine. Your diet should be nutritionally balanced, and your daily intake of fat, carbohydrates, and protein should be distributed over three main meals.


Orlistat has not been studied in pregnant women. However, orlistat may decrease the amount of certain vitamins that your body can absorb from the food you eat. Make sure you have discussed with your doctor the use of this medication during pregnancy.


It is not known whether orlistat passes into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.


Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of orlistat in children with use in other age groups.

Older adults

There is no specific information comparing use of orlistat in the elderly with use in younger adults. However, this medicine is not expected to cause different side effects or problems in older people than it does in younger adults.

Other medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking orlistat, it is especially important that your health care professional know if you are taking the following:

    • Warfarin-Orlistat may decrease the absorption of vitamin K and may change your bleeding time

Other medical problems

The presence of other medical problems may affect the use of orlistat. Make sure you tell your doctor if you have any other medical problems, especially:

    • Kidney stones or

    • Gallbladder problems-Orlistat may make the condition worse


Orlistat prevents the absorption of some of the fat you eat. Therefore, you should take it during the meal or within 1 hour of eating. If you occasionally miss a meal or eat a meal that contains no fat, you should skip the dose of orlistat.

Because orlistat may decrease the amount of some vitamins that your body can absorb from food, you will need to take a multivitamin supplement once a day. Take the vitamin supplement at least 2 hours before or after taking orlistat.


The dose of orlistat will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of orlistat. If your dose is different, do not change it unless your doctor tells you to do so.

    • For oral dosage form (capsules):

      o For treatment of obesity:

        Adults-120 milligrams (mg) three times a day with meals containing fat.

        Children-Use and dose must be determined by your doctor.

Missed dose

If you miss a dose of orlistat after a fat-containing meal, skip that dose. Wait until your next meal, and take the medicine on your regular schedule. Do not double doses.


To store this medicine:

    • Keep out of the reach of children.

    • Store away from heat and direct light.

    • Keep the medicine from freezing. Do not refrigerate.

    • Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.


It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to check for unwanted effects.

For patients with diabetes: Weight loss may result in an improvement in your condition, and your doctor may need to change your dose of oral diabetes medicine or insulin.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Check with your doctor as soon as possible if any of the following side effects occur:

More common

Bodyache; chills; cough; fever; headache; nasal congestion; runny nose; sneezing; sore throat.

Less common

Tightness in chest; tooth or gum problems; troubled breathing; wheezing.


Bloody or cloudy urine; change in hearing; contagious diarrhea; difficult or painful urination; earache; frequent urge to urinate; pain in ear. Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:.

More common

Gas with leaky bowel movements; inability to hold bowel movement; increases in bowel movements; oily bowel movements; oily spotting of underclothes.

Less common

Anxiety; back pain; menstrual changes; rectal pain or discomfort.

After you stop using this medicine, your body may need time to adjust. Side effects caused by orlistat usually disappear within 2 to 3 days after stopping it.

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

June 28, 2002

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