Orlistat
In brief
- In the UK, the 60 mg strength of orlistat (alli/generic orlistat) is available from pharmacies without a prescription, while the 120 mg strength (Xenical and generics) is prescription-only.
- Orlistat is used for weight loss and weight maintenance as part of a reduced-calorie, lower-fat diet. It works by inhibiting gastrointestinal lipases, reducing the absorption of dietary fat in the gut.
- The usual dose is 120 mg three times daily with main meals for prescription use, or 60 mg three times daily with meals for the OTC version.
- The form of administration is a hard gelatin capsule taken orally.
- It starts working with the first doses, as it acts in the gut during digestion, although noticeable weight-loss effects usually take days to weeks.
- The duration of action covers the period of digestion after each meal, so it is taken with each main meal up to three times daily.
- Alcohol does not have a specific direct interaction with orlistat, but alcohol can interfere with weight-loss goals, so moderation is advisable.
- The most common side effects are oily spotting, flatulence, urgent or frequent bowel movements, and fatty or oily stools.
- Would you like to try Orlistat without a prescription?
Legal status and availability in the UK
In the UK, orlistat 60 mg capsules (alli) are pharmacy medicines available without a prescription, while orlistat 120 mg capsules (Xenical and generics) are prescription-only medicines (POM).
In our online pharmacy, orlistat is available without a prescription, with discreet delivery to the United Kingdom in 9–21 days.
Basic orlistat information
- INN (international nonproprietary name): Orlistat
- Brand names available in the United Kingdom: Alli, Xenical
- ATC code: A08AB01
- Forms & dosages: 60 mg capsule, 120 mg capsule
- Manufacturers in the United Kingdom: Roche, GlaxoSmithKline, and generic suppliers
- Registration status in the United Kingdom: Licensed (MHRA)
- OTC / Rx classification: 60 mg capsules – pharmacy medicine (P); 120 mg capsules – prescription-only medicine (POM)
Clinical effectiveness in the UK NHS context
How well does orlistat work once it is prescribed in real life?
In NHS-style weight-management care, the answer depends heavily on adherence.
When people take it regularly with a reduced-calorie, lower-fat diet, orlistat can support modest weight loss and better maintenance over time.
That is why GPs and weight-management services usually judge it over months, not days.
If a patient has only lost a small amount after a few months, that is not necessarily failure, but it may mean the plan needs tightening or the medicine should be reconsidered.
Oily stools or urgent bowel movements can interrupt work, commuting or school runs, and that practical burden is often what decides whether someone stays on treatment.
| Expected benefits | Common challenges |
|---|---|
| Supports modest long-term weight loss | GI side effects can be embarrassing |
| May help maintenance after initial loss | Needs a lower-fat eating pattern |
| Can fit alongside GP support | Works only if doses are taken with meals |
| May improve confidence as progress builds | Benefits are judged over months |
In practice, NHS prescribing decisions often sit alongside referral to a weight-management programme, with follow-up review appointments.
If the progress is not clinically meaningful, continued treatment is usually hard to justify.
Indications, approvals and when orlistat is used
What is orlistat actually approved for, and when is it used?
It is approved for obesity and weight management, alongside diet and lifestyle changes.
The ATC code is A08AB01; alli 60 mg is the non-prescription pharmacy strength in the UK, and Xenical 120 mg is the usual prescription strength.
- Obesity treatment
- Used when a patient needs support with weight reduction together with diet and exercise changes.
- Weight maintenance
- Used after initial loss if the person is continuing to benefit and can keep to the diet plan.
- Pharmacy use
- Alli 60 mg is the lower-dose version available from pharmacies without a prescription.
| Strength | Status | Typical use |
|---|---|---|
| 60 mg | Pharmacy medicine (P) | Self-care weight management with diet changes |
| 120 mg | Prescription-only medicine (POM) | Obesity and maintenance under clinical supervision |
Off-label interest can exist in private clinics, but approved use should stay the focus.
It is not recommended for children under 12 years.
Composition, brands and UK product landscape
Are Alli and Xenical different drugs, or just different packs?
They contain the same INN, orlistat, but the dose and route of access differ.
Orlistat is usually supplied as hard gelatin capsules, and common pack sizes include 21, 42, 84 and 90 capsules, depending on brand.
Orlistat is also known chemically as tetrahydrolipstatin.
Roche is linked with Xenical, while GlaxoSmithKline is linked with Alli, and generic versions are also available.
| Brand / naming | Strength | Packaging notes |
|---|---|---|
| Alli | 60 mg | Hard gelatin capsules; OTC branding |
| Xenical | 120 mg | Hard gelatin capsules; prescription branding |
| Generic orlistat | 60 mg or 120 mg | Pack size varies by manufacturer |
Contraindications, precautions and daily-life restrictions
Is orlistat suitable for everyone?
No, and that is where pharmacist screening matters.
- Do not use if there is a chronic malabsorption syndrome, hypersensitivity to orlistat or excipients, or pregnancy.
- Not recommended for children under 12 years.
- Use caution with a history of oxalate kidney stones, diabetes, thyroid disease, renal impairment or hepatic impairment.
- Monitor closely if ciclosporin is being taken, because ciclosporin levels may fall.
| Avoid | Use caution | Monitor |
|---|---|---|
| Pregnancy | Kidney stone history | Ciclosporin levels |
| Chronic malabsorption | Diabetes | Blood glucose as weight changes |
| Allergy to the product | Thyroid disease | Symptoms of poor tolerance |
There is no sedative effect and no direct driving restriction.
That said, urgent bowel movements can make a long drive awkward, so many patients plan ahead.
Alcohol has no major direct interaction, but the overall diet still matters more than the drink itself.
Dosage guidelines and treatment duration
How should orlistat be taken for the best chance of success?
The answer is simple, but people often get it wrong at first.
Prescription Xenical 120 mg is taken three times daily with main meals.
Alli 60 mg is also taken three times daily with main meals.
If a meal is missed, or if the meal contains no fat, the dose should be skipped.
Do not double up later.
| Strength | Timing | Missed-dose advice |
|---|---|---|
| 120 mg | With main meals, or up to one hour after eating | Skip if no meal or no fat is eaten |
| 60 mg | With main meals, or up to one hour after eating | Skip if no meal or no fat is eaten |
Treatment is usually long-term when it is helping and when the diet is working.
In UK counselling, the key question is not “Has it worked in a week?”, but “Is meaningful loss being maintained over time?”
If not, the regimen needs review.
Interactions overview: food, drink and medicines
What matters most with orlistat interactions?
Food does.
Higher-fat meals usually trigger more GI side effects, so the diet is part of the interaction profile rather than an afterthought.
Tea and coffee do not have a known major direct interaction, although eating patterns around them may influence tolerance.
Ciclosporin levels may fall, so monitoring is needed if that medicine is being used.
Diabetes medicines may need review as body weight changes, and thyroid therapy may also need observation.
Suspected adverse reactions can be reported through the MHRA Yellow Card scheme.
| Interaction type | Concern | Action |
|---|---|---|
| Food | High-fat meals increase bowel side effects | Reduce fat intake with meals |
| Ciclosporin | Levels may fall | Monitor levels and response |
| Diabetes treatment | Needs may change with weight loss | Review therapy with the prescriber |
| Thyroid treatment | Observation may be needed | Monitor clinically |
Comparable medicines and patient preferences
Why do some people choose orlistat while others ask about semaglutide or liraglutide?
It usually comes down to mechanism, access and side effects.
Orlistat’s gut action can appeal to patients who want to avoid centrally acting medicines.
The downside is the bowel effects.
GLP-1 medicines such as liraglutide and semaglutide are injectable and may be preferred for appetite control, but they come with different monitoring needs and availability constraints.
| Medicine | How it works | Common patient preference point |
|---|---|---|
| Orlistat | Peripherally acting, gut-based | Non-systemic option, but GI effects can be limiting |
| Liraglutide (Saxenda) | GLP-1 agonist | Appetite-focused, but injectable |
| Semaglutide (Wegovy/Ozempic) | GLP-1 agonist | Often discussed for stronger weight-loss effects |
| Naltrexone/bupropion (Mysimba) | CNS / opioid antagonist combination | Different mechanism, prescription-only |
NHS obesity drugs are also prioritised differently from private care, which is why one person may get orlistat while another is assessed for a GLP-1 option.
Orlistat FAQ
How quickly does orlistat work?
It works from the first meals, but weight loss is judged over weeks and months, not overnight.
What if I eat a low-fat meal or miss a dose?
Skip that dose and do not double up later.
Is Xenical the same as orlistat?
Xenical is the 120 mg branded prescription version of orlistat.
Pregnancy is a contraindication, and diet changes still matter even when the medicine is being used.
Proper use, pharmacist counselling and support resources
What do pharmacists usually explain before someone starts treatment?
They usually keep it practical.
- Take the capsule with meals.
- Keep dietary fat lower to reduce oily stools and urgency.
- Expect treatment to work best as part of a structured lifestyle plan.
- Do not use it as a shortcut around diet.
- Seek review if side effects persist or progress is poor.
- Storage
- Keep below 25°C, away from moisture and direct sunlight.
- Overdose
- Large overdoses have not been linked with severe toxicity; supportive care is usually enough.
- When to seek help
- Ask for medical review if bowel effects are persistent, the diet is not sustainable, or another medicine such as ciclosporin is involved.
NHS patient portals and pharmacy consultation services are useful for reminders, follow-up and practical advice.
That support is often what helps someone turn a short trial into a sustainable plan.
Delivery across the United Kingdom
| City | Region | Delivery time |
|---|---|---|
| London | England | 9–21 days |
| Birmingham | England | 9–21 days |
| Manchester | England | 9–21 days |
| Leeds | England | 9–21 days |
| Glasgow | Scotland | 9–21 days |
| Edinburgh | Scotland | 9–21 days |
| Liverpool | England | 9–21 days |
| Bristol | England | 9–21 days |
| Cardiff | Wales | 9–21 days |
| Belfast | Northern Ireland | 9–21 days |
| Nottingham | England | 9–21 days |
| Leicester | England | 9–21 days |
| Sheffield | England | 9–21 days |
| Aberdeen | Scotland | 9–21 days |
| Plymouth | England | 9–21 days |
