Orlistat (P medicine)

This pharmacy guide helps pharmacy teams supply orlistat OTC safely and quickly within authorised use.

Published: 17 May 2023

Updated: 26 November 2025

This was published when the organisation was the Royal Pharmaceutical Society.

Sections on this page

Orlistat
Decision-making process for supply
Quantity to supply and repeat requests
Counselling
Record-keeping
Summary of product information
Obesity
Alternative treatments
Practical advice
Confidence in consultation skills
Further information

Orlistat

Orlistat is a potent, specific and long-acting gastrointestinal lipases inhibitor.

Further information on the mode of action can be found in the relevant summary of product characteristics (SPC) and patient information leaflet (PIL) under further information.

It works by blocking the absorption of approximately 25% of dietary fat. It can help achieve steady, gradual weight loss when used as directed.

Decision-making process for supply

You’ll need to use your professional judgement when dealing with requests (see our professional judgement guide).

It’s important to share information about the process of supply with the person requesting. Explain that you’ll need to ask some questions to make sure the medicine is suitable for them. And that you may need to refer them to a prescriber if you identify contraindications or if investigations are required.

You may want to use the following questions to support with suitability, prescreening, education and supply. Explore the person’s situation by considering and asking the following:

Who’s requesting a supply? Is it the person who needs the medicine or a representative?
- Supply to the person needing the medicine – is the person needing the medicine aged 18 years or older? Ensure you are supplying the medicine within the marketing authorisation.
- Supply to the person’s representative – see section on supplying to a person’s representative.
What is the person’s body mass index (BMI)?
- Always check the person’s BMI on each occasion orlistat OTC is requested and at the time of supply (BMI must be more than 28kg/m²).
Is the person hypersensitive to any of the active ingredients or excipients in orlistat capsules OTC?
- Orlistat is contraindicated if there is hypersensitivity to the active substance or any excipients listed.
Is the person pregnant or lactating?
- Orlistat cannot be used while breastfeeding or in pregnancy.
Do they have any health or medical conditions, and are they taking any medicines?
- Check for contraindications, interactions and any reason for referral under the summary of product information.
Have they already been supplied orlistat pharmaceutical (P) medicine OTC?
- Check if they experienced any side/adverse effects that would require referral to the prescriber, and see the repeat supply section.
Have they requested orlistat OTC in the past and been refused, or had to stop treatment for any reason?
- Find out why and use your professional judgement to decide if it’s a reason for referral.
Have they already been prescribed orlistat?
- Orlistat can still be purchased OTC if more practical (e.g. they are unable to get a suitable appointment with their prescriber). But, consider if an emergency supply of the person’s prescribed medicine is more appropriate (e.g. if they are being prescribed off-licence or under 18 years old) See our guide on emergency supply.
Are they aware of all the other options available to them?
- See the section on alternative treatments.
Use your professional judgement to decide on suitable action:
- If you feel the supply is suitable and the person requesting the medicine is happy to continue, provide counselling and relevant information using the section on summary of product information.
- If you feel the supply isn’t suitable, if in doubt of suitability or if medical attention, investigations or a referral is required, then refer to a prescriber.

Quantity to supply and repeat requests

You should use your professional judgement on a case-by-case basis to decide if frequent or multiple-pack supply to the same person is appropriate.

Quantity

There is no limit on the number of packs that you can sell.

However, the manufacturer of Alli (orlistat) recommends:

A review of the treatment at intervals of approximately three months (12 weeks) – if they haven’t lost any weight in that time, they may need to be assessed to determine whether continued treatment is appropriate.
You ensure that the person has a BMI more than 28kg/m² – on each occasion orlistat OTC is requested, at the time of supply.
That the treatment course shouldn’t exceed six months.

Repeats

You need to be satisfied that the medicine is still clinically appropriate and suitable on each occasion, and check if anything has changed since the last supply. You can ask to see if the person has evidence of the initial/previous consultation or supply (e.g. a slip to confirm where and when the consultation took place). This will determine if a repeat supply is suitable or if they’ll need a full consultation.

Consider the following questions to assess continued suitability:

Who is requesting the supply and how old are they?
Ensure that the person is aged 18 or over.
How long have they been using this medicine, and is there any improvement with use?
When was the last time they checked their BMI, and what was it?
Have there been any changes in their health or medical conditions since their last supply?
- Have there been any changes to their medicines (including prescribed, OTC, herbal products, complementary, vitamins, dietary supplements, recreational, alcohol and tobacco) since their last supply?
Have they experienced any side effects or signs and symptoms of adverse effects?
- Serious side/adverse effects may require immediate withdrawal and referral to the prescriber.

If you feel the supply is no longer suitable, if in doubt of suitability or if medical attention, investigations or referral is required, then refer to a prescriber.

If you feel the supply is suitable, then provide counselling.

Supply to the person’s representative

Orlistat OTC can be supplied to a representative. However, it is important that you only supply the product:

Within the marketing authorisation.
If you are satisfied it is a genuine request.
If the treatment is clinically appropriate for the person.

You’ll need to use your professional judgement with requests from representatives.

Consider the following:

Who is requesting on the person’s behalf and why?
How will you ensure that the treatment is clinically appropriate for the person needing the medicine (e.g. check contraindications, referrals, previous medical history and existing medicines)?
How can you get in touch with the person to assess suitability and determine whether the request is appropriate and genuine (e.g. by telephone)?
Be careful not to disclose to the representative what was previously discussed, unless you have consent from the person needing the medicine.
Are you supplying the medicine within the marketing authorisation (e.g. ensure that the person is aged 18 or over and that their current BMI is more than 28 kg/m² on each occasion orlistat OTC is requested)?
Use your professional judgement to decide how best to do this.

Counselling

Advise the person to read the PIL and packaging as a reminder of key safety messages.

Discuss the following:

The condition – explain the condition and what causes it, in order to empower the person to understand their condition (see the section on obesity).
Alternative treatments – provide information on alternative treatment options (see the section on alternative treatments).
The medicine – what it is, how it works and how to use it.
Importance of adherence:
- Most weight loss occurs within the first six months. However, consider if orlistat OTC should be continued if the person has not lost any weight in the first three months.
Side/adverse effects and risks – make sure the person is aware of what signs and symptoms to look out for and when to seek medical attention and advice.
Interactions – make sure the person knows to check interactions with a pharmacist before starting any new medicines and supplements (see the section on interactions).
Referrals – make sure the person is aware when to see a prescriber.
Offer practical advice – see the section on practical advice.
Health promotion – provide lifestyle and wellbeing advice (NHS) where appropriate, including diet, exercise, smoking cessation, and weight and blood pressure management.

You may also find our pharmacy guide on counselling people on the use of medicines useful.

Additional considerations

Here are some further points to consider when supplying:

Record-keeping – see the section on record-keeping.
Quantity to supply and how to obtain further supplies – make sure the person is aware of how to obtain further supplies. See the section on quantity to supply and repeat requests.
Online purchases – highlight the risks of purchasing medicines online:
- If buying from unregulated resources, the medicines may not be tested for safety or effectiveness.
- Advise the person to check that the medicine is being supplied from a reputable provider before purchasing (see the guidance from the General Pharmaceutical Council (GPhC) on internet pharmacy).
Online pharmacies – will need to meet GPhC regulatory standards for providing services at a distance (see the GPhC guidance on providing pharmacy service at distance, including on the internet, and GPhC premises standards).
Storage and disposal – advise the person to return any unused medicines to a pharmacy for disposal.
Delivering and posting medicines – the Medicines, Ethics and Practice (MEP) covers some additional points about delivering and posting medicines to patients.

Record-keeping

There is no legal requirement to make a record of the supply of a P medicine. However, professionally, you may decide to make a record of the following for audit purposes:

Referrals
Discussions
Advice you gave in terms of when and how to seek help if needed (i.e. safety netting)
Reasons for the advice that you gave.
Repeat sales
If the person has asked you to contact their prescriber
Interaction checks

If you decide to make a record, make sure you get the person’s consent (see GPhC guidance on confidentiality and consent).

Our pharmacy guide on clinical documentation may also be useful.

Summary of product information

The table below provides some product information on orlistat 60mg capsules for supply as a P medicine.

Refer to the full up-to-date product details in the relevant SPC and the British National Formulary (BNF), which can be found under further information.

Indication	– Weight loss in adults who are overweight or obese (BMI of more than 28kg/m²). – Aged at least 18. – Should be taken in conjunction with a low-fat and mildly hypocaloric diet.
When to refer	People should be referred to a clinician/prescriber if there is any doubt that the medicine is suitable for them and there are no other alternative OTC products available, or if the person: – Experiences any side effects – Has been unable to lose weight after 12 weeks of treatment – Has a contraindication – Is pregnant or breastfeeding – Is taking or using medicine(s) that has a clinically significant interaction with orlistat – Reports rectal bleeding while taking orlistat – Has been using orlistat for six months or longer – treatment shouldn’t exceed six months – Has kidney disease
Dose	– Take ONE 60 mg capsule three times daily. – Don’t take more than three 60 mg capsules in 24 hours (maximum daily dose is 180 mg). – It’s recommended that a diet and exercise programme is started before beginning treatment with orlistat, and continued when treatment with orlistat is stopped. – Treatment shouldn’t exceed six months.
Administration	– Take with water immediately before, during or up to one hour after each main meal. – Omit the dose of orlistat if a meal is missed or contains no fat.
Contraindications	Orlistat OTC is not recommended in the following: – Children or adolescents below the age of 18 years old. – People with cholestasis – blocked bile flow from the liver. – Chronic malabsorption syndrome. – Concurrent treatment with ciclosporin. – Concurrent treatment with warfarin or other oral anticoagulants. – Known hypersensitivity to the active substance or to any of its excipients. – People who are pregnant or breastfeeding.
Side/adverse effects	Very common – mainly gastrointestinal – Fatty, oily and soft stools – Flatulence – Oily leakage from rectum – Urgency to go to the toilet Common – Abdominal pain – Anxiety – Faecal incontinence – Increased defaecation – Liquid stools Advise people that gastrointestinal side effects are less likely to occur if they eat a lower fat diet. Effects typically occur within the first few weeks and tend to settle with time. You can refer to the BNF and relevant product SPC and PIL for further information on side effects. Report any suspected side effects via the Yellow Card scheme on the MHRA website. See our Yellow Card guide for further details.
Interactions	People taking the following medicines should be referred to their prescriber: – Acarbose – not recommended. – Amiodarone – the dose of amiodarone may need adjusting as orlistat may decrease plasma levels of amiodarone. – Antiretrovirals – orlistat may reduce the absorption of antiretrovirals. – Antiepileptics – increased risk of convulsions. – Antidepressants, antipsychotics (including lithium) and benzodiazepines – orlistat may reduce the efficacy of these medicines. – Ciclosporin – contraindicated as may decrease plasma levels of ciclosporin, which could lead to decreased immunosuppressive efficacy. – Levothyroxine – risk of hypothyroidism. – Medicines for diabetes – dose may need adjusting as weight loss may be accompanied by improved metabolic control. – Medicines for hypercholesterolaemia – dose may need adjusting as weight loss may be accompanied by an improvement of cholesterol levels. – Medicines for hypertension – dose may need adjusting as weight loss may be accompanied by an improvement in blood pressure. – Oral anticoagulants (including warfarin) – contraindicated as may affect international normalised ratio. Other: – Oral contraceptives – orlistat may indirectly reduce the availability of oral contraceptives and lead to unexpected pregnancy. Advise to use an additional method if severe diarrhoea is experienced. – Soluble vitamins (A, D, E and K) – orlistat may impair absorption so advise to take multivitamin supplement at bedtime to help ensure adequate vitamin intake. Refer anyone with a clinically relevant interaction to their prescriber, using your professional judgement. For the full list of interactions, see the BNF, Stockley’s Drug Interactions and relevant product SPC and PIL
Pregnancy and breastfeeding	– Cannot be used while breastfeeding. – Cannot be used in pregnancy.
Age	For use in adults over 18 years old.
Storage	– Do not store above 25°^C. – Keep the container tightly closed to protect from moisture.

Obesity

According to the World Health Organization, obesity is defined as “abnormal or excessive fat accumulation that presents a risk to health.”

Obesity can be caused by many factors. For example:

Diet – extra calories from high-fat and high-sugar diets are stored in the body as fat.
Lack of physical activity.
Genetics – affecting how your body uses food and stores fat.
Health conditions – for example, uncontrolled hypothyroidism.
Medicines – (e.g.,) steroids, antidepressants, antipsychotics, diabetes medicines.

There are different tools that can be used to check if you are a healthy weight, including:

BMI – measures if you are a healthy weight for your height. You can use the NHS healthy weight calculator to find out your BMI. For further information on BMI ranges and limitations, see the NHS website.
Waist-to-height ratio – for adults who have a BMI under 35. A waist-to-height ratio of 0.5 or higher means you may have increased health risks.
Being overweight can increase the risk of developing other health problems, such as:
- Type 2 diabetes mellitus (T2DM)
- Stroke
- Some types of cancers
- Heart disease
- Mental health problems – low confidence, self-esteem and mood
- Breathlessness
- Sweating more and mobility issues
- Snoring
- Tiredness
- Joint and back pain

Alternative treatments

People should also be made aware of all the treatment options available in addition to orlistat OTC, as something else may be more suitable, and so they can make an informed choice. Consider referring the person to their doctor if alternate treatments are more suitable.

Alternative pharmacological treatments include:

Tirzepatide (Mounjaro)
Semaglutide (Wegovy)
Liraglutide (Saxenda)

These weight-management injections are prescribed by a healthcare professional (HCP). They work by making you feel full, reducing your appetite and slowing down gastric emptying. You will need to eat a balanced, reduced-calorie diet and exercise regularly while taking these medicines.

Alternative non-pharmacological treatments include:

Diet – eating a balanced, reduced-calorie diet (you may want to seek advice from an HCP with expertise in weight-loss management).
Exercise regularly – for example, cardio-type exercise like fast walking, jogging, or swimming for 150 to 300 minutes (2.5 to 5 hours) a week.
Surgery – bariatric surgery can help people with severe obesity, but they need to meet certain criteria to be eligible.
Support – for example, joining a local weight-management programme or seeking counselling/coaching from a trained HCP to help you understand your relationship with food and develop better eating habits.

Practical advice

Promote a healthy lifestyle including diet and exercise

It is recommended that a nutritionally balanced diet and exercise programme is started before treatment – provide advice to people on diet and discuss how to incorporate some light exercise into their daily routine to improve overall health and support weight loss.
Advise the person on a low-fat and mildly hypocaloric diet – containing approximately 30% of calories from fat (e.g. on a 2,000kcal per day diet, this would be less than 67g of fat per day).
Consumption of a lower-fat diet will help with weight loss and minimise diet-related gastrointestinal side effects.
When the person stops taking orlistat OTC, they should continue with a healthy diet and exercise to maintain weight loss.

Highlight the benefits of weight loss

Advise that being overweight increases the risk of developing health problems such as (T2DM) and heart disease.

Expectations

Advise that orlistat OTC is not a quick fix for weight loss. Realistic weight-loss targets are usually between 0.5kg and 1kg per week (one to two pounds) – you may want to consider offering to monitor the person’s weight as a way of keeping them motivated.
Orlistat OTC, alongside a reduced-calorie, low-fat diet:
- Can help you lose around 5% to 10% of your initial body weight over time (over 12 months).
- May help you lose 50% more weight than if you just dieted alone (i.e. if you lose 2lbs with diet and exercise, orlistat can help you lose 1lb extra).

Offer diagnostic screening

Use your professional judgement to decide which method to use to check the person’s BMI (e.g. information on the product’s packaging, a height/weight chart or offer to measure the person’s height and weight as part of a weight management service).
There is also an opportunity for pharmacy teams to provide diagnostic testing and screening services (e.g. cholesterol, diabetes, blood pressure, as appropriate).

Confidence in consultation skills

Discussing weight loss may be uncomfortable for some people, who may feel nervous approaching the pharmacy team. To ensure comfort and confidence, the pharmacy team should always be discreet, non-judgemental and put the person at ease.

If a request needs to be referred to you by counter staff, they will need suitable training to handle such circumstances, since they are usually the first point of contact. Referrals should also be covered in the standard operating procedure.

To support these conversations, good communication is essential. Develop your confidence with practical tips and information in our consultation skills pharmacy guide. You may also find our resource on facilitated self-selection of P medicines helpful.

Further information

RCPharm

Clinical

Consultation skills

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