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Orlistat (Alli/Xenical)

Orlistat, also known under the brand names Alli and Xenical, is an oral weight loss medication. Take orlistat alongside your meals to reduce the amount of dietary fat absorbed into your body by a third.

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*Ratings based on our prescribers’ own experience with medications provided and are not a reflection of your own suitability for treatment.

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Taking Orlistat for Weight Loss

If you’re not crazy about injecting yourself with a medication like Wegovy or Saxenda, a weight-loss treatment like Orlistat could be the perfect choice for you.

Although you don’t have to inject it, the differences in how this medication works could sway your decision when you’re thinking your treatment options through.

We’re going to have a good look at what Orlistat is, how it works, and how effective it can be when it comes to helping you drop the pounds.

What is Orlistat?

Orlistat is a type of weight loss medication known as a fat binder and it’s available in capsules that are taken with your food.

You may not recognise the name Orlistat, but you may be familiar with some of the medications which use Orlistat as their active ingredient — some of the most popular brands are Alli, Xenical, and Orlos.

It’s clinically proven to help you lose up to 50% more weight than dieting alone when you pair it with a calorie-controlled diet and an exercise plan.

Basically, it takes all of the hard work you’re putting into your weight loss plan and helps you to get more out of it.

Like other weight-loss medications, it’s only recommended for those who have a BMI of 28 and above as a way to help you reach a healthy weight.

How does Orlistat work?

As a fat binder, Orlistat does exactly what it says on the tin.

You take this medication with a main meal and the active ingredient binds to the fat from your food so your body can’t break it down and digest it.

This fat is then passed out of your body with your poo.

By working in this way, Orlistat keeps your body from digesting up to a third of the fat that’s in your food, effectively reducing your fat intake and helping you lose weight in the process.

Think of Orlistat as your diet’s best friend, when you make the effort to reduce your calorie intake and eat less fat, this medication can help you make progress more quickly.

How long does Orlistat take to work?

Orlistat capsules work right away, so they’ll start to reduce your fat intake from the very first dose.

However, this doesn’t mean that you’ll drop 50lbs in a day (if it did it would be a miracle!), it simply means that it will be as effective as possible from the word go.

Naturally, you’ll need to consume fewer calories to lose weight, and this in itself will take time, but Orlistat can be the helping hand you need to drop those pounds.

After 12 weeks of treatment, you should have lost at least 5% of your starting body weight, so if you started treatment weighing 260lbs, you should lose at least 13lbs over 12 weeks.

How to take Orlistat

You should always take Orlistat as your prescriber or pharmacist has recommended, but you’ll usually take one 120mg capsule with each of your 3 main meals during the day.

You can take it before, with, or after your meal, depending on what works best for you.

If you’re eating a meal with 0 fat content or skip a meal for any reason, you don’t need to worry about taking your capsule — if there’s no fat for Orlistat to bind to, it won’t have anything to do anyway!

Titration Path

When you first take Orlistat you’ll need to get used to how your body reacts to this treatment and the changes you’re making to your diet.

This is why our prescribers recommend that some patients start off by taking two capsules a day, instead of the maximum three – having that one meal a day without Orlistat can be a big relief during this adjustment period.

Of course, you should always follow the dosage instructions given to you by your prescriber and remember to ask if there’s anything you’re unsure about.

When you reach this stage in your treatment plan you’ll be taking one Orlistat capsule with each of your three main meals – so three 120mg capsules a day.

You’ll continue on this dose as you continue your weight loss journey with Orlistat, form healthier new habits, and maintain the progress you made during the early stages of your treatment.

Does Orlistat have side effects?

Yes, Orlistat can have side effects, just like any other medication you may be taking.

One of the most well-known side effects of this medication is oily discharge or fatty poo, which can be a bit off-putting if you’ve never taken Orlistat before.

The reason this side effect happens is that your body needs to pass out the fat that hasn’t been digested in your system, and as you know, there’s only one way out!

Normally, this fat will come out in your poo, making it a bit softer or fattier than usual, but if you’ve eaten a meal with high-fat content then there’s going to be more fat for your body to get rid of.

Naturally, your body still has to get rid of all this undigested fat, which is when you would experience discharge, oily flatulence (wind or gas), or a lot of fat in your poo.

This can be avoided by sticking to a low-fat diet and spreading your fat intake out throughout your 3 main meals every day, to reduce the amount of fat your body needs to get rid of.

Other common side effects you may experience while taking Orlistat include:

  • Headaches
  • Abdominal pain or discomfort
  • Low blood sugar in those with type 2 diabetes
  • Pain or discomfort in your back passage
  • Soft stools, incontinence
  • Bloating, especially in those with type 2 diabetes
  • Tooth or gum disorders
  • Changes to your periods
  • Tiredness

Your diet plan – Foods to avoid and foods you’ll love

As you may have realised by now, your diet will be an essential part of your weight loss journey with Orlistat.

If you want to avoid the side effects caused by excess undigested fat, you should try to eat a lower-fat diet, a good rule of thumb is that your fat intake should be around 30% of your calorie intake.

When spread over 3 meals a day, this will work out at around 12 – 19g of fat in each meal, although the ideal amount can be different from person to person.

With that in mind, we recommend avoiding fatty foods, using as little oil as possible when cooking, and removing as much fat as you can from cuts of meat.

If you’re unsure, the nutritional information table included on your food packaging can help you decide whether it’s something you want to include in your Orlistat diet.

On the other hand, low-fat foods will be your new best friend — think fruits, veggies, lean white fish and chicken breast, and low-fat dairy options.

Seasonings and spices contain very little to no fat too, so it’s time to stock up your spice rack and try out some new recipes!

Can you take Orlistat and Saxenda together?

We don’t recommend taking Orlistat and Saxenda at the same time.

These are both weight loss medications that work in different ways, and taking both could lead to losing too much weight too quickly or other unpleasant side effects.

The same goes for Wegovy, a similar weight loss injection to Saxenda.

The only time an exception to this rule could be considered is if you’re taking Liraglutide (the active ingredient in Saxenda) as a treatment for type 2 diabetes, rather than weight loss.

That being said, it’s highly unlikely that your prescriber would recommend Orlistat if you’re already taking Liraglutide, or vice versa.

How much is this treatment?

Your consultation with myBMI costs £59*, and that covers absolutely everything – your consultation with our team of medical professionals, your treatment, and any supporting treatments you may need to help you manage side effects.

During your consultation, you’ll discuss your treatment options with our healthcare team, and if they think Orlistat is right for you, they’ll be happy to help you start your medication and your weight loss journey.

*If you decide to change to a different treatment after a consultation, the cost of our services may change to reflect the cost of your medication.

Content Written By

Laura Henderson

Laura Henderson

Reviewed & Fact-Checked

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How to Take Orlistat for Weight Loss

Taking Orlistat at the right time is very important, so let us help you get it right! We look at doses, timing, and how long treatment lasts.

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