Alli is available after consultation with a pharmacist or as a prescription only medicine. Our clinicians review each treatment request on an individual basis, and prescriptions are subject to a clinical decision after completing our online consultation. This page is only intended for those who have completed an online consultation and have been prescribed Alli.

We would like to provide you with important information before you start taking Alli. It is also recommended to read the patient information leaflet to understand how the medication works, what to expect, and potential side effects and how to manage them.

Alli is a capsule formulated medication that can help you lose weight if you are overweight. It suits people who prefer swallowing a capsule rather than other administration techniques when taking medication for weight loss. The way it works is partially dependent on your diet, and so are the potential side effects. To help you understand all the important aspects of orlistat and the side effects, keep on reading.

Alli alters the way consumed fat is metabolised in the stomach and in the small intestine. When we eat, enzymes from the stomach and pancreas are released into the gastrointestinal system to break down the food we eat into smaller molecules. By doing this, the enzymes help the body absorb the food we eat.

Alli works by blocking enzymes called lipase that break down dietary fats. When the fat can’t be broken down to absorbable smaller components, they are left in the gastrointestinal system and removed in the stools. Clinical studies have shown that orlistat blocks about 25-33% of consumed fats. This effect may result in weight loss since the dietary fats are not being absorbed by the body, but it can also cause some of the common side effects of orlistat.

Alli is suitable for patients with:

Alli should be used with a nutritionally balanced, reduced calorie diet that contains approximately 30 % of calories from fat. It is recommended that the diet should be rich in fruit and vegetables. The daily intake of fat, carbohydrate and protein should be distributed over three main meals.

One Alli capsule should be taken with water immediately before, during or up to one hour after each main meal. If a meal is missed or contains no fat, the dose of orlistat should be omitted.

Alli should be taken a maximum of three times a day.

The effect of Alli results in an increase in fat in stools as early as 24 to 48 hours after taking it.

Treatment with Alli may potentially affect the absorption of fat-soluble vitamins (A, D, E and K). For this reason, a multivitamin supplement should be taken at bedtime.

If you take more capsules than you have been told to take, seek medical attention from your GP or 111.

Alli performs its effects in the gastrointestinal system causing the undigested fats to go through the entire system instead of being absorbed. Unfortunately, this can also cause side effects which in most cases affect the gastrointestinal system. These include:

Other potential side effects that affect other part of the body are:

The gastrointestinal side effects of Alli are generally mild and transient. The fats in the stools usually appear as early as 24 to 48 hours after dosing. If the treatment is discontinued, the stool returns to your normal standard within 48-72 hours.

Remember to always read the patient information leaflet before starting your treatment. It has listed all important information about the medication, the potential side effects and gives you an in depth understanding of if the medication is suitable for you.

Keep the blister in the outer carton in order to protect from light and moisture. Do not store above 25 °C.

Capsule filling:

Capsule shell:

If you have any questions about taking Alli please get in touch by emailing [email protected]. If you feel unwell and feel you need urgent medical attention please call NHS 111 or attend your nearest accident and emergency department.

This is a non-promotional, safety information page for Alli. If you are interested in weight management treatment, please reach out to our clinical team by contacting [email protected].