Orlistat (Xenical)

Orlistat 120 mg is a safe and effective medicine that is used to aid weight loss and help prevent weight gain for people who have already lost weight. It is a medicine that is used in conjunction with a weight loss programme and a balanced diet and exercise plan. Orlistat 120 mg works on the digestive system by preventing the fat in the food we eat being absorbed by the body.

What is Orlistat 120 mg?

Orlistat 120 mg is a medicine that can help with weight loss if you have been diagnosed as obese or overweight (with a body mass index of 28 or more) and have other medical conditions that can be affected by excess weight such as high blood pressure, diabetes, high cholesterol or heart disease. Body mass index (BMI) is the weight of a person in relation to their height. Orlistat 120 mg is also suitable for weight loss if you have a body mass index of 28 or more, do not have the conditions mentioned above, but are at risk of developing these health problems which can be serious.

Some overweight people find using Orlistat 120 mg to lose weight helps with motivation as it can achieve faster results than just by dieting and doing exercise alone. However, Orlistat 120 mg cannot be used in isolation to lose weight – it must be used in conjunction with a healthy diet. If a weight loss of 5% of the total body weight is not achieved within 12 weeks, you should discontinue using Orlistat 120 mg and talk to your doctor.

Orlistat 120 mg stops the body absorbing approximately 3% of the fat from the food eaten. It works by inhibiting two enzymes called pancreatic and gastric lipases that usually break down the fat in the intestines. These enzymes exist in the digestive juices and normally turn the fat into molecules that the bloodstream absorbs via the gut.

When you take Orlistat 120 mg, it is not absorbed directly into your bloodstream. Usually, the body either converts the fat you eat into body tissue (causing excess weight) or energy. Orlistat 120 mg stops this happening and the excess fat that Orlistat 120 mg prevents the body from absorbing is excreted via faeces, as it prevents the body from digesting it. The active ingredient in this medicine is orlistat.

When is Orlistat 120 mg used?

Orlistat 120 mg is for adults (over 18 years old) who are obese or overweight, with a body mass index of 28 or more. It should be taken in conjunction with a healthy diet that monitors and controls fat and calorie intake. Lifestyle changes are important when losing weight and it is also essential to take regular exercise in combination with taking this medicine and dieting. Orlistat 120 mg can be used by people wishing to lose weight for the first time if they are overweight or obese, or by those who have been unsuccessful in reducing their weight with diet and exercise alone.

How do you take Orlistat 120 mg?

Orlistat 120 mg comes in capsule form and the normal dose is one capsule with water three times a day before, during or after a main meal. Orlistat 120 mg should only be taken with meals that contain fat or it will not be effective. However, this does not mean meals that have a high fat content. As part of this weight loss programme, you should eat three balanced meals a day. These meals should be more or less equal in their quantities of fat, protein and carbohydrates. It is advisable to start your healthy eating programme a few days before you begin to take your Orlistat 120 mg medication so that your body can get used to the change in diet. It is important to read the labels of the food you buy. This will help you plan your meals and balance your nutritional intake when using Orlistat 120 mg.

It is important to eat healthily when trying to lose weight. To do this you should:

  • Choose foods with a fat content of less than 30%;
  • Buy lean meat;
  • Remove the skin from chicken;
  • Use skimmed or semi-skimmed milk;
  • Cook with vegetable oil spray or olive oil;
  • Buy low-fat versions of products;
  • Serve yourself smaller portions (a trick is to use a smaller plate).

You should avoid eating processed food, ready meals, fast food and anything that has a high fat content. Also, you should avoid fatty foods such as sugary or savoury snacks between meals as eating these could counteract the effect of Orlistat 120 mg. Do not take extra capsules (i.e. more than three per day) if you eat something containing fat between meals as this could be dangerous. Some people find it helpful and motivational to keep a food diary when losing weight. You record everything you eat and your weight so you can keep a track of your weight loss.

If you miss a meal, do not take an Orlistat 120 mg capsule. You should wait until your next meal that contains fat and only take one capsule as normal, do not take an extra capsule to make up for the missed one.

What dosages are there?

The usual dosage of Orlistat 120 mg is three separate 120 mg tablets per day before, during or after meals that contain fat. This applies to adults who are overweight or obese with a body mass index of 28 or over. However, do not purposely eat foods high in fat content when taking this medicine as the side effects could increase. Your fat intake should be controlled and balanced to assist the weight loss, in conjunction with regular exercise. Orlistat also comes in 60 mg capsules. When taking Orlistat fat burn pills, you should see a reduction in your weight after 12 weeks. If not, you should talk to your doctor. You should not use Orlistat for more than six consecutive months.

What are the side effects of Orlistat 120 mg?

As with all medicines, Orlistat 120 mg may have some side effects. However, not everyone will experience these.

The most common side effects are:

  • Oily or fatty stools;
  • Abdominal pain / discomfort;
  • Flatulence (wind) with or without discharge;
  • Urgent or increased need to open the bowels;
  • Incontinence (stools);
  • Low blood sugar levels (experienced by some people with type 2 diabetes);
  • Bloating (experienced by some people with type 2 diabetes);
  • Anxiety;
  • Headaches.

Most of these effects, particularly those related to the stomach, are caused due to the way this medicine works. In particular, you may notice a change to your bowel habits when taking Orlistat 120 mg. This is likely to be in the form of oily or fatty stools, which is due to the fat you have eaten not being digested and being excreted. This is normal and no cause for concern.

Orlistat 120 mg can sometimes block the body’s absorption of certain vitamins and beta carotene. Beta carotene is found in fruit and vegetables and converts to vitamin A, which is essential for health. If you are concerned about your vitamin absorption when taking Orlistat 120 mg, you should talk to your doctor as they may suggest a vitamin supplement. If you take a vitamin supplement, it should be a multivitamin that includes vitamins A, D, E and K. It is important to take this when you are not taking an Orlistat 120 mg capsule: last thing at night is a good time.

Please read the package leaflet for any other possible side effects. If you experience any of the side effects above and they are particularly uncomfortable, please see a doctor.

When should you not take Orlistat 120 mg?

You should not take Orlistat 120 mg if you:

  • Are allergic to any of the ingredients in the package leaflet;
  • Are under 18 years of age;
  • Have a body mass index of less than 28;
  • Are taking blood-thinning medication;
  • Have cholestasis (when the flow of bile between the liver and intestines is blocked);
  • Suffer from malabsorption (when your body does not absorb enough nutrients);
  • Are planning to become pregnant, are pregnant or are breastfeeding.

If you have any kind of kidney disorder, it is important to talk to a doctor before Orlistat 120 mg as it may be linked to kidney stones. If you are taking any other medication, even herbal medicines, you should consult a doctor or pharmacist before taking Orlistat 120 mg. This medicine does not have an effect on your ability to drive or use machinery.

Does Orlistat 120 mg interact with other medication?

It is possible that Orlistat 120 mg may interact with other medication, including herbal medicines. If you are taking any other medicines, you should talk to a doctor before taking Orlistat. This includes other weight loss medication.

Where can you buy Orlistat tablets?

Orlistat tablets are available from pharmacies nationwide. You can purchase in store or order online.

Can I get Orlistat tablets without a prescription?

You require a prescription to obtain Orlistat 120 mg, which is the usual recommended dose. You can however buy Orlistat 60 mg without a prescription.


Obesity. Treatment. 16 May 2019. Retrieved 6 July 2019 from

Orlistat. 27 March 2014. Retrieved 6 July 2019 from

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