3.1 Orlistat

Orlistat 60mg capsules are available OTC for use by over-18s whose BMI is 28kg/m2 or greater with a low-fat reduced-calorie diet and regular exercise. Around 5% weight loss is reported after a year’s use (with lifestyle changes). It is taken three times daily with or after food. Orlistat inhibits gastric lipases so that around one-third less fat is digested and absorbed with more excreted in the faeces.

Orlistat is also available on NHS prescription (POM) at a higher dose (120mg with meals, three times daily), and is usually only recommended where the person has made a significant effort to lose weight through diet, exercise or lifestyle changes.

NHS prescriptions for orlistat increased from 294,000 in 2020 and reached 545,000 in the year to June 2025. However, in most parts of England prescribing has plateaued.

GI adverse effects are very common (e.g. oily spotting, abdominal discomfort, increased flatulence, faecal urgency, fatty stools). Bowel movements may become frequent or urgent and cases of faecal incontinence and anal leakage of oil can occur, which can be embarrassing for your customer. Taking drugs for diarrhoea (such as loperamide) will not control these symptoms. They usually reduce with continued use of orlistat due to careful monitoring of limited fat intake. 

If the person has not lost weight after 12 weeks of treatment with orlistat, it is recommended that treatment is stopped. Orlistat reduces the absorption of fat-soluble vitamins.

In most people levels remain within the normal range if a healthy diet rich in vegetables and fruits is being eaten. If in doubt, a multivitamin supplement can be taken and this needs to be at least two hours after the orlistat, typically at bedtime.

Weight loss variable

The amount of weight loss achieved with orlistat varies. In clinical trials, where the 120mg dose was used with dietary change and exercise, patients lost 2.9kg more on average compared with placebo and dietary change, over one year. After orlistat was stopped, a significant number of people regained weight.

People who took orlistat showed improvement in their blood pressure, cholesterol levels and blood sugars.

In a longer-term clinical trial, fewer people developed type 2 diabetes over four years. A Cochrane systematic review of the use of orlistat in people with hypertension found moderate-confidence evidence that orlistat reduces weight and BP.

For many customers, the weekly injection offered by semaglutide or tirzepatide is considered more convenient compared to multiple daily doses of orlistat — and it is always important to consider how the dosing schedule will fit with their lifestyle and preferences.