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Prescription weight loss treatment facts

Prescription weight loss treatment facts

About prescription weight loss treatments

We can offer either Saxenda, Orlistat or Xenical as prescription treatment to help you lose weight. We’ll help you decide if treatment is right for you, and how you need to take it to get the best results.

How do the treatments work?

Saxenda works by reducing your appetite and making you feel fuller. You inject Saxenda under your skin using an injection pen. You can see how to inject it on the How to use Saxenda page.

Xenical is the branded version of Orlistat. These tablets both work in the same way — by blocking the absorption of some of the fat from your meal. Your body then gets rid of the fat through your stool. The medicines are best used alongside a lower fat healthy eating plan. Eating less fat at meal times while taking your treatment can help to reduce any potential side effects of the medicine.

Please see our ‘Eating when on Saxenda, Orlistat or Xenical’ guides for extra tips on losing weight successfully.

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How do I take weight loss medicine?

If you’re prescribed Saxenda, you’ll need to inject it just under the skin. You’ll probably find this is easier than you first think. Saxenda should be used once a day, at around the same time. Best injection sites are your tummy area (abdomen), the front of your thighs or your upper arm. Saxenda needs to be stored in the fridge.

Orlistat and Xenical are tablet medicines. You take a single tablet with water, immediately before or up to one hour after a main meal. You can take your prescribed treatment up to three times a day. If you miss a meal, or have a meal that does not contain fat, you should not take Orlistat or Xenical at that time.

What are the side effects?

These medicines have some potential side effects. These include headaches and increased anxiety.

With Saxenda the common side effects are nausea, vomiting, diarrhoea and constipation. There can also be an increased heart rate and an increased risk of gallstones.

There are also some common side effects with Orlistat or Xenical that are caused by the extra fat being passed out through your stool. These include abdominal pain, oily diarrhoea, the urgent need to use the toilet, wind, and anal leakage. When used with the recommended low fat approach to your meals, these side effects can be reduced. There can also be headaches and increased anxiety.

For the full information on a medicine’s side effects and how to take it, it’s important to read the Patient Information Leaflet that comes with your medicine.

How quickly does weight loss treatment work?

Both Orlistat and Xenical treatments start to work the first time you take a tablet with a meal. It will block some of the fat from being absorbed by the body.

Saxenda starts working straight away, and you should see the effects within 2 weeks.

How long does it take to lose weight with weight loss treatment?

If you take your treatment as recommended with a low fat food plan, you can expect to lose at least 5% of body weight over three months. It’s important to remember that although these medicines can help, changing your lifestyle and eating habits is what will sustain a healthy weight over the long term.

Important safety information

Please tell us which other medicines you’re taking — whether they’re prescription or medicines you’ve bought without a prescription. We need to know so that we can prescribe treatment, if it’s suitable for you. If you’re taking certain medicines or living with certain medical conditions, this service might not be suitable for you.

What are my options if I don’t want medication?

There are things that you can do to manage your weight without medication. Improving your diet and increasing your activity can both help with weight loss and help you to live a healthier, happier life. Our webinars may help you too.

Keeping you safe

If you do not feel safe, are experiencing abuse or control, or have experienced this in the past, please find support below or send us a message:

Page last reviewed by: Dr. Christina Hennessey 23/08/2021