Alli (orlistat) capsules
Updated over a week ago

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.

What is Alli and how does it work?

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.

How does Alli work?

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.

How to tell if Alli is suitable for you

Alli is suitable for patients with:

  • A BMI of more than or equal to 28

Don’t take Alli if you…

  • have chronic malabsorption syndrome

  • have cholestasis

  • are pregnant or breast-feeding

  • are allergic to Alli or any of the ingredients inside the capsule (see What Alli contains section)

  • are taking ciclosporin

  • are taking warfarin or any other anticoagulant

How to use Alli

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.

What to do if you take more Alli than you should

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

Side-effects of Alli

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:

  • Oily spotting visible on your underclothes

  • Gas with discharge - wet fart

  • Urgent or increased need to open bowels

  • Fatty oily stool

  • Soft or liquid stools

  • Stomach pain

  • Faecal incontinence - leakage of stools

  • Bloating (in patients with Type 2 diabetes)

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

  • Headache

  • Fatigue (a feeling of tiredness and lack of energy)

  • Anxiety

  • Upper or lower respiratory infection

  • Urinary tract infection

  • Irregularity in periods

  • Tooth disorder or gingival disorder

  • Low blood sugar (in patients with Type 2 diabetes)

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.

Stop using Alli and consult your GP if you notice any of these side effects

  • If you have an allergic reaction (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 (symptoms include abdominal pain and tenderness, nausea, vomiting, fever, constipation)

  • Bleeding from the back passage (rectum)

  • 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.

  • Gallstones. Symptoms can include sudden and rapid pain, pain between shoulder blades or right shoulder, nausea and vomiting, yellowing of skin and whites of eyes, itching

  • Pancreatitis (inflammation of the pancreas). Symptoms can include severe, sudden pain in the center of the stomach, fever, nausea and vomiting.

How to store Alli

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

What Alli contains

Capsule filling:

  • microcrystalline cellulose (E460)

  • sodium starch glycolate (type A)

  • povidone (E1201)

  • sodium laurilsulfate

  • talc

Capsule shell:

  • gelatine

  • indigo carmine (E132)

  • titanium dioxide (E171)

  • sodium laurilsulfate

  • sorbitan monolaurate

  • polysorbate 80

  • indigo carmine (E132)

  • printing ink (black iron oxide,shellac, propylene glycol)

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].

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