Xenical / Orlistat

Xenical and generic Orlistat contain the active ingredient orlistat at 120mg per capsule. They are prescription-only medicines that work in your digestive system by preventing about a third of the fat in each meal from being digested. They attach to the enzymes that usually break down fat; any undigested fat passes out of your body when you go to the toilet. They do not work through the brain’s appetite centres in the same way as some other weight-loss medicines.

In many clinical trials, when taken with diet and exercise, orlistat has been shown to support greater weight loss than diet and exercise alone.¹

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The usual dose is one 120 mg capsule taken with each of your three main meals per day. You can take it immediately before, during or up to one hour after a meal.

To support effective, long-lasting results, combine Xenical/Orlistat with exercise and the right diet. You need a balanced, calorie-controlled diet rich in fruit and vegetables, with no more than about 30% of calories from fat. Carbohydrate, protein and fat should be spread evenly across your three daily meals, and you should try to avoid fat-containing snacks such as biscuits, chocolate or crisps between meals.

If you miss a meal or have a meal with no fat, you do not need a dose, as the medicine only works when there is fat in your meal.

If you miss a dose you can take it within an hour of your meal, but do not take a double dose.

Tell us if, for any reason, you have not taken your medicine exactly as prescribed. Otherwise we may think it was not effective or well tolerated and may change your treatment unnecessarily. We will usually discontinue treatment after 12 weeks if you have not lost at least 5% of your starting body weight.

You should take a daily multivitamin supplement alongside Xenical/Orlistat. Some vitamins and minerals are fat-soluble; if you do not digest all the fat in your diet you could become deficient.

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As with all medicines, Xenical/Orlistat can cause side effects, although not everyone gets them. You may notice changes to your bowel movements because more fat passes through your digestive system. These changes are often mild and most common in the first few weeks. Typical symptoms can include increased wind, more frequent bowel movements and oily discharge. If you eat meals higher in fat than the recommended limit, you may find bowel control harder. Over time, symptoms often reduce, especially if you follow the recommended diet.

Always tell a doctor or pharmacist as soon as possible if you do not feel well while you are taking Xenical/Orlistat.

Very common side effects (affects more than 1 user in 10)

• Headache
• Abdominal pain or discomfort
• Urgent or increased need to open the bowels
• Flatulence (wind) with discharge
• Oily discharge, oily or fatty stools
• Liquid stools
• Low blood sugar levels (experienced by some people with type 2 diabetes)
• Upper respiratory infections
• Flu (influenza)

Common side effects (affects 1 to 10 users in 100)

• Rectal pain or discomfort
• Soft stools
• Incontinence (stools)
• Bloating (experienced by some people with type 2 diabetes)
• Tooth or gum disorders
• Irregularity of menstrual cycle
• Tiredness
• Anxiety
• Lower respiratory infections
• Urinary tract infections

The following side effects have also been reported but their frequency cannot be estimated from the available data:

• Allergic reactions. The main symptoms are itching, rash, wheals (slightly elevated, itchy skin patches that are paler or redder than surrounding skin), severe difficulty in breathing, nausea, vomiting and feeling unwell
• Skin blistering (including blisters that burst)
• Diverticulitis
• Bleeding from the back passage (rectum)
• Increases in the levels of some liver enzymes may be found in blood tests
• Hepatitis (inflammation of the liver). Symptoms can include yellowing skin and eyes, itching, dark coloured urine, stomach pain and liver tenderness (indicated by pain under the front of the rib cage on your right-hand side), sometimes with loss of appetite. Stop Xenical/Orlistat if such symptoms occur and tell your doctor
• Gallstones
• Pancreatitis (inflammation of the pancreas)
• Oxalate nephropathy (build-up of calcium oxalate which may lead to kidney stones)

Xenical/Orlistat can also affect other medicines you are taking, such as anticoagulants. Always tell the doctor about all your medicines and read the patient information leaflet fully before you start taking Xenical or Orlistat.

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