Orlistat (By mouth)


Orlistat (OR-li-stat)
Used as part of a diet plan to help you lose weight and to help keep the lost weight from returning.

Brand Name(s)

There may be other brand names for this medicine.

Xenical, Alli

When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to orlistat, or if you have gallbladder disease, or a disorder that keeps you from absorbing or digesting food.

How to Use This Medicine

  • Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
  • Take this medicine with a liquid during each main meal or up to one hour after eating.
  • This medicine comes with patient instructions. Read and follow these instructions carefully. Ask your doctor or pharmacist if you have any questions.
If a dose is missed:
  • If you miss a meal or eat a fat-free meal, you can skip your dose of the medicine.
  • If you forget to take the medicine with a meal, you may take it up to 1 hour after eating. If it has been longer than 1 hour since eating, do not take the medicine. Wait until it is time for your next dose to take the medicine.
  • Do not use extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any leftover medicine after you have finished your treatment. You will also need to throw away old medicine after the expiration date has passed.
  • Keep all medicine away from children and never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
  • Make sure your doctor knows if you are taking cyclosporine (Gengraf®, Neoral®, Sandimmune®). Cyclosporine must be used at least 2 hours before or 2 hours after you use orlistat.
  • Tell your doctor if you are using dietary supplements (including herbal products). You may be told to use a multivitamin that contains vitamins D, E, and K, and beta-carotene. Extra vitamins may be needed because orlistat keeps you from absorbing certain kinds of vitamins from food. If you use multivitamins, take them at least 2 hours before or 2 hours after taking orlistat. You may want to take your multivitamin at bedtime.
  • Tell your doctor if you are also using levothyroxine (Levothroid®, Levoxyl®, Synthroid®). Levothyroxine must be used at least 4 hours before or 4 hours after you take this medicine.
  • Your doctor should know if you are also using medicine to treat diabetes (such as insulin, glyburide, glipizide, metformin, Glucophage®, or Glucotrol®), or any other medicines to help you lose weight.

Warnings While Using This Medicine

  • Make sure your doctor knows if you are pregnant or breastfeeding, or if you have heart disease, kidney stones, underactive thyroid, or an eating disorder (such as anorexia or bulimia).
  • Make sure your doctor knows if you have diabetes. Your doctor may need to change your diabetes medicine if you change your diet or lose weight.
  • This medicine works by keeping your intestines from absorbing some of the fats from food. The undigested fat goes out of your body in your bowel movements.
  • The amount of fat calories in your meals should be no more than 30% of the total calories for each meal. Side effects can be worse if you eat a meal that has a high amount of fat. Divide your daily intake of fat evenly over your 3 main meals each day.
  • Carefully follow your doctor's instructions about a reduced-calorie diet and regular exercise. Talk with your doctor or health caregiver about a healthy and well-balanced eating plan that you should follow. Ask your doctor or health caregiver before starting any exercise program.
  • Contact your doctor if you or your child have pain or tenderness in the upper stomach, unusual itching, yellowing of the eyes or skin, dark-colored urine, loss of appetite, or light-colored stools while taking this medicine. These may be signs of a liver problem.
  • This medicine may cause a serious type of allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Call your doctor right away if you or your child have a rash; itching; hoarseness; trouble breathing; trouble swallowing; or any swelling of your hands, face, or mouth while you are using this medicine.
  • Your doctor will need to check your progress at regular visits while you are using this medicine. Be sure to keep all appointments. Blood tests may be needed to check for unwanted effects.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:
  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.
  • Change in how much or how often you urinate.
  • Dark-colored urine or pale stools.
  • Nausea, vomiting, loss of appetite, or pain in your upper stomach.
  • Red or dark brown urine.
  • Severe diarrhea.
  • Severe stomach pain with nausea and vomiting.
  • Sharp back pain just below the ribs.
  • Yellowing of your skin or the whites of your eyes.
If you notice these less serious side effects, talk with your doctor:
  • Back pain.
  • Changes in menstrual periods.
  • Feeling unable to control bowel movements, or feeling like you need to have a bowel movement right away.
  • Fever, chills, cough, runny or stuffy nose, sore throat, and body aches.
  • Headache or dizziness.
  • Increase in how often you have a bowel movement.
  • Joint or muscle pain.
  • Mild diarrhea or stomach pain.
  • Oil or fat in your bowel movements.
  • Passing gas with your bowel movements.
  • Passing oil from your rectum.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
Review Date: 2011-02-04 Reviewed By: Keywords: ,
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