What is this medicine?
Orlistat (OR li stat) is used to help people lose weight and maintain weight loss while eating a reduced-calorie diet. This medicine decreases the amount of fat that is absorbed from your diet.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): alli, Xenical
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 disease
- HIV or AIDS
- kidney stones
- liver disease or hepatitis
- organ transplant
- pancreatic disease
- problems absorbing food
- stomach or intestine problems
- thyroid disease
- take medicines that treat or prevent blood clots
- an unusual or allergic reaction to orlistat, other medicines, foods, dyes, supplements or preservatives
- pregnant or trying to get pregnant
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 within 1 hour after each 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. Use of this medicine without a prescription is not approved in children less than 18 years.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
What if I miss a dose?
If you miss a dose, take it within 1 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. If you occasionally miss a meal or have a meal without fat, you can skip that dose of this medicine.
What may interact with this medicine?
- antiviral medicines for HIV or AIDS
- certain medicines for hepatitis
- certain medicines that treat or prevent blood clots like warfarin, enoxaparin, dalteparin, apixaban, dabigatran, edoxaban, and rivaroxaban
- medicines for diabetes
- medicines for seizures
- other medicines or products for weight loss
- supplements like vitamins A, D, E and K
- thyroid hormones
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medicine?
Do not use this medicine if you have had an organ transplant. This medicine interferes with some of the medicines used to prevent transplant rejection.
This medicine can cause decreased absorption of some vitamins. You should take a daily multivitamin that contains normal amounts of vitamins D, E, K and beta-carotene or vitamin A. Take the multivitamin once per day at bedtime 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. Follow a well-balanced, reduced-calorie, low fat diet. Try starting this diet before taking this medicine. Following a low fat diet can help reduce the possible side effects from this medicine.
Do not use this medicine if you are pregnant. Losing weight while pregnant is not advised and may cause harm to the unborn child. Talk to your health care professional or pharmacist for more information.
This medicine may cause a decrease in vitamin D. You should make sure that you get enough vitamin D while you are taking this medicine. Discuss the foods you eat and the vitamins you take with your health care professional.
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
- breathing problems
- bloody or black, tarry stools
- signs of infection like fever or chills
- signs and symptoms of kidney stones like blood in the urine; pain in the lower back or side; pain when urinating
- signs and symptoms of liver injury like dark yellow or brown urine; general ill feeling or flu-like symptoms; light-colored stools; loss of appetite; nausea; right upper belly pain; unusually weak or tired; yellowing of the eyes or skin
- trouble passing urine or change in the amount of urine
- uncontrolled, urgent bowel movements
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
- increased number of bowel movements
- oily stools (bowel movements may be clear, orange or brown in color)
- stomach discomfort, gas
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medicine?
Keep out of the reach of children.
Storage at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Keep container tightly closed. Throw away any unused medicine after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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