Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Xenical (Orlistat). If you are concerned about side effects, discuss the risks and benefits of Xenical (Orlistat) with your doctor.

The following side effects have been reported by at least 1% of people taking Xenical (Orlistat). Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• discoloured stools
• Diarrhea
• gas with discharge
• inability to control bowel movements
• increases in bowel movements
• oily or fatty stools
• oily spotting of underclothes
• urgent need to have a bowel movement

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• signs of kidney problems (e.g., increased urination at night, decreased urine production, blood in the urine, swelling of the hands or feet, painful urination)
• swelling of feet or ankles
• symptoms of gallstones (such as pain in the upper right part of the abdomen that may be accompanied by nausea and vomiting)
• symptoms of Kidney Stones (such as back pain and blood in the urine)
• symptoms of liver damage (e.g., abdominal pain, clay-coloured stools, dark urine, loss of appetite, yellow skin or eyes)
• symptoms of low blood sugar (e.g., cold sweat, cool pale skin, headache, fast heartbeat, weakness

Stop taking the medication and seek immediate medical attention if any of the following occur:

• bleeding from the rectum
• signs of an allergic reaction (e.g., Hives, shortness of breath or difficulty breathing, swelling of the eyes, mouth, lips, or throat)
• signs of pancreatitis (e.g., abdominal pain on the upper left side, back pain, nausea, Fever, chills, rapid heartbeat, swollen abdomen)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Xenical (Orlistat).

Each turquoise capsule, with "Roche Xenical 120" printed in black ink, contains 120 mg of Xenical (Orlistat). Nonmedicinal ingredients: gelatin, indigo carmine, microcrystalline cellulose, povidone K30, sodium lauryl sulfate, sodium starch glycolate, talc, and titanium dioxide.

Do not take Xenical (Orlistat) if you:

• are allergic to Xenical (Orlistat) or any ingredients of the medication
• have cholestasis (a condition where bile excretion in the liver is stopped)
• have chronic malabsorption syndrome (a condition where you do not absorb nutrients from food properly)

There may be an interaction between Xenical (Orlistat) and any of the following:

• Amiodarone
• beta-carotene
• birth control pills
• Calcitriol
• certain diabetes medications (e.g., glyburide, Gliclazide, insulin, metformin)
• Cyclosporine
• fat-soluble vitamin supplements (e.g., vitamin A, vitamin D, vitamin E, and vitamin K)
• Levothyroxine
• oral anticoagulants (e.g., Warfarin)
• Propafenone
• seizure medications (e.g., Carbamazepine, Phenytoin, Phenobarbital)

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Xenical (Orlistat). Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription) and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

Before you begin taking a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Xenical (Orlistat).

Diabetes: If you have type 2 diabetes and are taking Xenical (Orlistat) in combination with other diabetes medications, you may be more at risk of experiencing Hypoglycemia (low blood sugar). If you experience hypoglycemia symptoms such as sweating, dizziness, shakiness, hunger, or confusion, contact your doctor. Your doctor may need to adjust the dose of your medication(s). You should continue to monitor your blood sugar levels regularly.

Fat intake: It is very important to follow recommended dietary guidelines while taking Xenical (Orlistat). The risk of side effects associated with the stomach (such as gas with discharge or oily spotting of underclothes) increases when Xenical (Orlistat) is taken with a high-fat diet. Your daily intake of fat should be distributed over three main meals and should not be more than 30% of the total calories. Discuss with your doctor or dietitian if you have any concerns or questions regarding how to manage your diet.

Gastrointestinal problems: If you have bowel or rectal problems, discuss with your doctor how Xenical (Orlistat) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Xenical (Orlistat), and whether any special monitoring is needed. Bleeding from the rectum has been reported with the use of Xenical (Orlistat). If this occurs, contact your doctor as soon as possible.

Kidney stones: If you have a history of kidney stones, discuss with your doctor how Xenical (Orlistat) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Xenical (Orlistat), and whether any special monitoring is needed.

Liver: There have been rare reports of severe liver injury in people taking Xenical (Orlistat). If you experience any symptoms such as loss of appetite, yellow skin or eyes, abdominal pain, dark urine, light-coloured stools, or pain in the upper right part of the abdomen, contact your doctor immediately.

Seizures: Xenical (Orlistat) may interact with seizure medications by decreasing the amount of seizure medication that your body absorbs. This can result in increased seizures. If you have a history of seizures, discuss with your doctor how Xenical (Orlistat) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Xenical (Orlistat), and whether any special monitoring is needed.

Thyroid: Xenical (Orlistat) may affect how well your thyroid gland works, possibly by reducing the amount of iodine available from your diet for your body to produce thyroid hormone. If you have Hypothyroidism (low thyroid hormone levels), your doctor should closely monitor your condition while you are taking Xenical (Orlistat), as it may affect thyroid levels.

Vitamins: Xenical (Orlistat) may reduce the absorption of beta-carotene and fat-soluble vitamins such as vitamin A, vitamin D, vitamin E, and vitamin K. Talk to your doctor or pharmacist about taking a multivitamin supplement. If you are already on a multivitamin, take it at least 2 hours before or after taking Xenical (Orlistat), or take it at bedtime.

Pregnancy: Xenical (Orlistat) has not been adequately studied in pregnant women. Xenical (Orlistat) should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking Xenical (Orlistat), contact your doctor immediately.

Breast-feeding: It is not known if Xenical (Orlistat) passes into breast milk. If you are a breast-feeding mother and taking Xenical (Orlistat), it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of Xenical (Orlistat) have not been established for use in children less than 12 years of age.