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Orlistat Oral capsule

Orlistat (OR li stat) is used to help obese people lose weight and keep the weight off while eating ... more

Generic Name: orlistat

Brand Names: Alli, Xenical

There is an FDA Alert for this drug. Click here to view it.

What is this medicine?

Orlistat (OR li stat) is used to help obese people lose weight and keep the weight off while eating a reduced-calorie diet. This medicine decreases the amount of fat that is absorbed from your diet.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • an eating disorder, such as anorexia or bulimia
  • gallbladder problems or gallstones
  • problems absorbing food
  • an unusual or allergic reaction to orlistat, other medicines, foods, dyes, supplements or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Take this medicine with each main meal that contains about 30 percent of the calories from fat or one hour after the meal. Do not take your medicine more often than directed. If you occasionally miss a meal or have a meal without fat, you can skip that dose of this medicine.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed. While this drug may be prescribed for children as young as 12 years for selected conditions, precautions do apply.

What if I miss a dose?

If you miss a dose, take it within one hour following the meal that contains fat. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

  • cyclosporine
  • dietary supplements like beta-carotene and vitamins A, D, E, and K
  • thyroid medicine
  • warfarin

What should I watch for while using this medicine?

Changes in your eyesight, skin or hair may be signs of a vitamin deficiency. Since this medicine can cause decreased absorption of some fat-soluble vitamins, you may need to take a daily multivitamin that contains normal amounts of vitamins D, E, K and beta-carotene. Take the multivitamin once per day at least 2 hours after your dose of this medicine unless otherwise directed by your doctor or healthcare professional.

You should use this medicine with a reduced-calorie diet that contains no more than about 30 percent of the calories from fat. Divide your daily intake of fat, carbohydrates, and protein evenly over your 3 main meals. You should try to follow a healthy eating plan like the one developed by the American Heart Association. Following this eating plan can help reduce the possible side effects from this medicine.

If you are taking levothyroxine, this medicine and levothyroxine should be taken at least 4 hours apart.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • arthritis or joint pain, tenderness
  • back pain
  • blood in the urine
  • breathing problems
  • dark urine
  • feeling faint. lightheaded
  • general ill feeling or flu-like symptoms
  • light-colored stools
  • loss of appetite
  • nausea, vomiting
  • right upper belly pain
  • uncontrolled, urgent bowel movements
  • unusually weak or tired
  • yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • clear, orange or brown colored bowel movements
  • increased number of bowel movements
  • oily stools
  • stomach discomfort, gas


Last Updated: July 06, 2010
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