Xenical (orlistat) is a prescription weight loss treatment available to help people suffering with obesity. Research has shown that Xenical can help people with a BMI of over 30 to lose between 5% and 10% of their body weight.

Please read the important information below before ordering

How does it work?

Xenical works by inhibiting lipase, an enzyme that breaks down the fat in your diet, preventing it being absorbed by your body as excess weight. This undigested fat then passes out of your body in the stool.

Xenical results in an increase in faecal fat content within 24 to 48 hours of starting treatment. After stopping treatment, faecal fat content usually returns to pre-treatment levels within 48 to 72 hours.

Orlistat does not block the absorption of calories from sugar and other non-fat foods.

Xenical is safer to use than many other weight loss medications as it works directly in your digestive system, rather than targeting your brain.

How do you take Xenical?

Xenical is easy to take, with one 120mg capsule taken with each meal. If a meal is missed or contains no fat, the dose of orlistat should not be taken.

Each prescription from MyClinic is valid for a 12 week supply of 120mg tablets.

Doses of Xenical above 120 mg three times daily have not been shown to provide additional benefit. 

Treatment with orlistat should be stopped after 12 weeks if you have been unable to lose at least 5 % of the body weight as measured at the start of treatment.

Please refer to the manufacturer's patient information leaflet for further guidance on taking Xenical.

Losing Weight with Xenical

While attempting to lose weight using Xenical, you should follow a reduced-calorie diet with a fat content of around 30%, rich in fruit and vegetables. The daily intake of fat, carbohydrate and protein should be distributed over three main meals.

Users typically notice an improvement in weight loss within two to three months of starting Xenical. However, weight loss can be aided by common-sense lifestyle changes such as exercising more and adopting a healthier diet.

Side-effects of Xenical

The most common side effect of Xenical is changes in bowel movement habits. This generally occurs during the first weeks of treatment, but can continue throughout treatment. If any symptoms are severe or do not go away please consult a doctor.

As with any medication, some side-effects can be serious. You should stop using Xenical and seek immediate medical advice if you experience any of the following:

  • hives, rash or itching
  • difficulty breathing or swallowing
  • severe or continuous stomach pain or back pain
  • pain in the upper right part of the stomach
  • excessive tiredness or weakness
  • nausea or vomiting
  • loss of appetite
  • drowsiness or confusion
  • mood changes
  • yellowing of the skin or eyes
  • urinating less than usual or not at all
  • dark coloured urine
  • light coloured stools

Orlistat can block your body's absorption of some fat-soluble vitamins and beta carotene. Therefore, when using orlistat you should take a daily multivitamin that contains vitamins A, D, E, K, and beta-carotene

Further Information

HSE Programme for Healthy Eating and Weight Management

Xenical (orlistat) patient information leaflet

Start Consultation

Dr Terry Deeny

Consult with our doctor online

How to use this service?

Fill out a questionnaire

A member of our medical team will then review your answers and if suitable send you a prescription by post.

Take your prescription to any Irish pharmacy to pay for the medication.

Your prescribing doctor's name and IMC registration number will be included on all prescriptions. 


MyClinic FacebookMyClinic Twitter