Medically reviewed on May 2, 2018.
Uses of Xenical:
- It is used to help you lose weight.
What do I need to tell my doctor BEFORE I take Xenical?
- If you have an allergy to orlistat or any other part of Xenical (orlistat).
- If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
- If you have any of these health problems: Gallbladder disease, malabsorption syndrome, or poor eating habits.
- If you are pregnant or may be pregnant. Do not take Xenical (orlistat) if you are pregnant.
This is not a list of all drugs or health problems that interact with Xenical (orlistat).
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take Xenical (orlistat) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take Xenical?
- Tell all of your health care providers that you take Xenical (orlistat). This includes your doctors, nurses, pharmacists, and dentists.
- Drugs used to treat seizures may not work as well while you take Xenical (orlistat). Call your doctor right away if your seizures happen more often or get worse while you take Xenical (orlistat).
- Liver problems have happened with Xenical (orlistat). Sometimes, this has been very bad and has led to the need for a liver transplant or death. Liver problems may happen in people with or without liver disease. Talk with the doctor.
- If you have high blood sugar (diabetes) and take drugs to lower blood sugar, talk with your doctor. Weight loss may raise the chance of low blood sugar if you take drugs to lower blood sugar. Call your doctor right away if you have signs of low blood sugar like dizziness, headache, feeling sleepy, feeling weak, shaking, a fast heartbeat, confusion, hunger, or sweating.
- Do not take more than what your doctor told you to take. Taking more than you are told may raise your chance of very bad side effects.
- This medicine may affect how much of some other drugs are in your body. If you are taking other drugs, talk with your doctor. You may need to have your blood work checked more closely while taking Xenical (orlistat) with your other drugs.
- If you are pregnant or you get pregnant while taking Xenical (orlistat), call your doctor right away.
- Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.
How is this medicine (Xenical) best taken?
Use Xenical (orlistat) as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take with each main meal that has fat or up to 1 hour after the meal.
- You may skip a dose if you miss a meal or if the meal does not have fat.
- Take vitamins at least 2 hours before or 2 hours after Xenical (orlistat). Bedtime may be a good time to take vitamins.
- This medicine may prevent other drugs taken by mouth from getting into the body. If you take other drugs by mouth, you may need to take them at some other time than Xenical (orlistat). Talk with your doctor.
- Follow the diet and workout plan that your doctor told you about.
What do I do if I miss a dose?
- Skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
See also: Dosage Information (in more detail)
What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of kidney problems like unable to pass urine, change in how much urine is passed, blood in the urine, or a big weight gain.
- Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
- Signs of gallstones like sudden pain in the upper right belly area, right shoulder area, or between the shoulder blades; yellow skin or eyes; or fever with chills.
- Black, tarry, or bloody stools.
- Pain when passing urine.
- Passing urine more often.
- Very bad back pain.
- Very bad groin or thigh pain.
- Very bad belly pain.
What are some other side effects of Xenical?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Loose stools (diarrhea).
- Not able to control stools.
- Gas with discharge, oily spotting, and feeling the need to go to the bathroom.
- Fatty or oily stools.
- Belly pain.
- Upset stomach.
- Back pain.
- Feeling tired or weak.
- Period (menstrual) changes.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.
See also: Side effects (in more detail)
If OVERDOSE is suspected:
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
How do I store and/or throw out Xenical?
- Store at room temperature.
- Keep lid tightly closed.
- Store in a dry place. Do not store in a bathroom.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
Consumer information use
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else's drugs.
- Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
- Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about Xenical (orlistat), please talk with your doctor, nurse, pharmacist, or other health care provider.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
More about Xenical (orlistat)
- Xenical Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Drug Images
- Drug Interactions
- Support Group
- Pricing & Coupons
- En Español
- 88 Reviews – Add your own review/rating
- Drug class: peripherally acting antiobesity agents
Other brands: Alli