Xenical (Orlistat) Tablets

Xenical is a branded version of Orlistat, a popular weight loss pill that works by attaching to certain enzymes in the body that break down fat. Xenical then stops the fat from being digested and absorbed, meaning that it helps reduce the calories consumed from the fat in the food and helps with weight loss. It is taken by mouth, like tablets and can be taken up to three times a day. When paired with a diet and lifestyle change, it can help people achieve weight loss. 

Xenical, UK’s branded version of orlistat tablets, is a prescription-only weight loss medication used to assist with weight loss and maintenance, in combination with a balanced diet and physical activity. It can be prescribed to those with a BMI over 30 kg/ m² (obesity) or those with a BMI of 28 kg/ m² with a weight-related health condition. 

At The Family Chemist, we always consider your BMI and medical history to determine treatment eligibility and safety.

Xenical’s active ingredient, Orlistat, acts on certain enzymes in the gut to stop the breakdown and absorption of fat that has been consumed during a meal. This way the calories absorbed from the food are lower and the fat is also not stored in the body, leading to eventual weight loss. Xenical will not work on existing fat in the body. 

The medication is known to block around one third of the fat from food eaten from being absorbed. Any fat that isn’t digested is then passed through your stools. If Xenical is taken with low-fat meals, it will not affect weight loss or make an impact.

Take one 120mg Xenical capsule with water, immediately before, during or up to 1 hour after each main meal.  

Don’t chew or break the capsule and swallow it whole. 

Eat a nutritionally balanced diet; the manufacturers advise that your meal should have no more than 30% of its calories from fat. This ensures that Xenical can help you lose weight while reducing the risk of side effects from the medication. 

If you miss a meal, or your meal contains no fat, just skip the Xenical pill with that meal.

In trials and studies, Xenical has shown that it can help people lose a modest, but meaningful amount of weight when it’s combined with a reduced-calorie diet and physical exercise. About 35-55% of people lost at least 5% of their starting body weight, and around 16-25% lost 10% or more of their weight. Xenical can give you an added boost to support steady, gradual weight loss. 

You should aim to lose 5% of your starting weight by week 12, however, the speed and quality of Xenical’s effects depend on your diet and lifestyle.

Xenical, like any other medication, can cause some side effects. Some of the very common (may affect more than 1 in 10 people) side effects are: 

• Abdominal pain or discomfort 

• Oily spotting or discharge from the back passage or fatty stools 

• More frequent, or urgent bowel movements 

• Headaches  

While taking Xenical, you may experience these side effects. A well-balanced diet with no more than 30% fat can help reduce the likelihood of the side effects persisting. 

The list above does not include all possible side effects, therefore it is vital that if you experience any serious side effects whilst using this medication to consult a healthcare professional and if you experience side effects not listed above, complete a MHRA Yellow Card report. 

Be sure to read through the patient information leaflet before taking any new medication to familiarise yourself with the possible side effects, cautions, and contraindications. You should only take Xenical capsules once you have understood all the warnings and precautions. If you are concerned discuss this with your doctor or a The Family Chemist clinician. 

If you miss a dose of your Xenical capsule, take it as soon as you remember if it’s been less than an hour since your last main meal. After that, you can continue taking it as normal. 

Do not double up the number of capsules to make up for a missed dose, as this only increases the likelihood of having side effects.

Xenical is a branded version of the medication Orlistat. There is no difference between the two medications other than the brand. Both treatments have the same active ingredient, come as the same strength of capsules and work in the same way.  

If you wish to switch from Xenical to Orlistat, you can stay on the same dose. 

It’s important to talk to your GP or prescriber if you’re wishing to switch your weight loss medication.

There are a range of alternative medications to Xenical that are licensed for use in the UK. These include weight loss injections, and weight loss tablets, which are available through The Family Chemist. All treatment options are provided alongside dietary and lifestyle changes.

If medicated options are not suitable for you, there are some alternative options to consider: 

1. Behavioural Therapy: Weight management often involves changes in diet and exercise habits. Behavioural therapy, either individually or in group settings, can provide valuable strategies and support for making lifestyle changes. 
2. Dietary Counseling: Working with a registered dietitian or nutritionist can help you develop a personalized meal plan that aligns with your weight loss goals and dietary preferences. 
3. Exercise Programs: Regular physical activity is essential for weight management. Consider engaging in an exercise program or working with a personal trainer to establish a fitness routine. 
4. Lifestyle Changes: Small but sustainable changes in your daily habits, such as portion control, mindful eating, and adequate sleep, can contribute significantly to weight loss. 
5. Surgical Options: In cases of severe obesity, surgical procedures like gastric bypass, gastric sleeve, or lap band surgery may be considered a last resort.  

No. It can be dangerous to take multiple weight loss medications at the same time. We cannot provide Xenical if you are already on other treatments. You can switch between treatments, but you must first consult your doctor and may be advised to have a sufficient treatment gap for your safety.

It’s essential to exercise caution and consult with your healthcare provider regarding alcohol consumption while taking Xenical or any medication.

When taking Xenical capsules, it’s important to reduce the amount of processed, greasy or fatty food. This includes fatty means, deep-fried food, crisps and pastries.  

This will help reduce the chances of you experiencing side effects while taking Xenical.

Xenical works to stop the absorption of fat from food and can reduce the absorption of some fat-soluble nutrients (such as vitamin D, E and beta-carotene). Because of this, and as with many other medications, it may interfere with other medications or make them less effective. It’s important to let us know your full medical history so that our clinicians can ensure Xenical is prescribed safely. 

To ensure you still have sufficient amount of nutrients, follow a well-balanced diet with considerable amounts of fruit and vegetables. Your doctor may suggest taking multivitamin supplements.

Xenical can reduce the absorption of contraceptive pills (e.g. mini pill or combined pill). If you experience severe diarrhoea or vomiting, you should use additional barrier methods or other forms of contraception during the time you’re experiencing these side effects and for up to 7 days after.

Orlistat safety update (2024) Medicines and Healthcare product Regulatory Agency [accessed 20th February 2026] 

Xenical emc [accessed 20th February 2026] 

Overweight and obesity management (2025) NICE guidelines NG246 [accessed 20th February 2026]