Orlistat Before and After – Weight Loss Results

Orlistat (brand names Xenical and alli) is a prescription weight loss tablet that helps 37% of people lose 5% or more of their starting weight within 12 weeks (about 3 months) of treatment. You take it whenever you eat a meal containing fat, up to 3 times a day. Taking orlistat changes how your body absorbs fat, and instead of storing excess fat, you remove up to a third from your body as waste (stool). By absorbing less fat, you take in fewer calories, making it an effective treatment for weight management.

Orlistat is clinically proven to help patients lose weight effectively and safely, with studies showing that patients taking orlistat for 6 months lose 5.6kg on average, compared to an average 2.4kg loss for those taking a placebo (a pill with no medication in). It’s a fast-acting treatment, with some patients beginning to see weight loss results after just 2 weeks.

Orlistat works by reducing how much fat your body absorbs from your meals, making it easier to lose weight when taken alongside a healthy diet and exercise plan. It does this because the active ingredient, orlistat, is a type of medication called a ‘lipase inhibitor’. Lipase breaks down fats in the body so they can be absorbed and stored as energy. When you don’t burn as much energy as you absorb, excess energy is stored as fat around your body and you gain weight.

Orlistat stops this from happening by binding to the lipases that help your body break down and absorb fat, which stops them from working, and instead of absorbing the fat, your body gets rid of it as stool waste. By doing this, orlistat stops you from absorbing around a third of the fat you usually would, which can help you burn more energy than you absorb leading to weight loss.

In weight loss studies, orlistat helped 37% of people lose 5% or more of their starting weight after taking it every day for 12 weeks. The same study also found that 49% of these people went on to lose 10% or more of their starting weight after a year of treatment.

Another study found that when combined with a healthier diet and exercise plan, orlistat can help people lose around 50% more weight than those on a placebo – with people on average shown to lose:

• 1.5kg or 3.3 pounds (lbs) after 8 weeks
• 4.5kg or 9.9lbs after 16 weeks
• 5.1kg or 11.24lbs after 24 weeks

This is compared to an overall loss of 2.5kg or 5.5lbs over 24 weeks on a placebo.

When taking orlistat, we recommend aiming for a loss of around 1 to 2 pounds (about 0.5 to 1kg) per week, and you might notice the effects of taking it within 2 weeks of starting treatment. However, it’s important to remember that weight loss takes time, and everyone’s body reacts differently to treatment. Other factors, like your starting weight, age, and medical history, can also affect how much weight you lose on orlistat and how quickly you do. So don’t be put off if your journey with orlistat looks a little different. Following your diet plan every day, exercising, and reducing how many calories you have in a day by 600 is the best way to make sure you lose weight with orlistat.

Your first month on orlistat:

Week 1

You should notice the effects of orlistat quickly (usually within 1 or 2 days), provided you remember to take it after each meal, up to 3 times a day, and stick to your diet plan. You may also notice some changes to your bowel movements as your body starts to remove more fat. Sticking to a low-fat diet can help to minimise these side effects.

You may see up to 1 or 2lbs of weight loss, but don’t be discouraged if you don’t. It can take up to 2 weeks or longer to start seeing results.

Week 2

By now, you’ll be getting more used to taking your treatment and sticking to your diet and exercise regime. You may also notice some minor side effects but these can be reduced by only eating around 30% of your daily calories in the form of healthy fats and splitting this evenly between each of your 3 orlistat meals.

Again, you can expect to lose around 1 to 2 lbs of weight but if you haven’t noticed any weight loss yet, keep with it as it can take up to 12 weeks to lose 5% of your weight.

Week 3

You should feel more comfortable with your treatment and be getting used to how it affects your body. If you are still experiencing side effects, now might be a good time to make any other small changes to alleviate or reduce them. You can review your diet and reduce the amount of fat in meals – 30% is just a guide and you can reduce this further if you need to, as long as you’re still getting some healthy fats into each meal as fat is a macronutrient and your body still needs some to function properly.

You may see 1 or 2lbs of weight loss, or even more. We all lose weight at different rates, and if you’ve reduced the amount of calories and fat in your diet and are exercising regularly, it's only a matter of time before you see consistent weight loss.

Week 4

By the end of your first month, you should be well on your way to losing weight with orlistat. You can expect to lose up to 10lbs and with fat reduction in your diet, should be able to reduce or limit side effects. You may still get some, but these should be mild and get better as you continue with treatment. If your side effects are still persisting even though you’ve reduced your fat intake, or they’re affecting your life, speak to your doctor or pharmacist.

Many factors can affect your results with orlistat, so not everyone loses the same amount of weight at the same rate. Try to remember this on your journey because this is your weight loss experience, and it's about finding safe and sustainable strategies that work for you long term.

Factors that affect orlistat results:

Age

Older people tend to lose weight slower than younger people. This can be due to muscle loss, hormone changes, less exercise, and slowing metabolism. So, if you are older, you might not lose weight at the same pace as someone much younger. This doesn't mean you won't lose weight at all, it just might take a little more time.

Diet

A healthy diet plays a huge role in how orlistat works, so if you're not sticking to your diet plan, you're not going to lose weight as effectively as someone who is. While orlistat helps your body remove more fat from your meals, it does not do so entirely. If you are still eating meals extremely high in fat, you will absorb some fat, which can lead to weight gain. You'll also be more likely to get side effects like loose stools, oily stools, and more frequent or urgent bowel movements.

Exercise

Exercising and moving more can help you lose weight alongside a healthy, balanced diet. The more calories your body burns, the less fat it stores in reserve. This is especially important to consider when taking orlistat, as you want to make sure you're burning the fat your body doesn't remove as waste. So, if you're less active or sit around a lot during the day, you will probably see different weight loss results than someone who is more active when taking orlistat.

You can improve these results by exercising around 5 days a week, as well as moving more, such as going for a walk on your lunch break or standing up every hour if you work at a computer.

Medical conditions and medications

Certain medical conditions and medications can affect how quickly you lose weight or make you gain weight. If you have a condition like diabetes, thyroid problems, or take a medication that causes weight changes, like corticosteroids, you might see different results with orlistat.

Your doctor will consider these conditions when prescribing treatment and work with you on a treatment plan, but it may mean you see different results compared to someone without these conditions.

How the medication affects you

Some people find one medication more effective than another or find that one causes fewer side effects. You may find your body doesn't respond as well to orlistat as you’d like. If this is the case, you might see different results or need to try a different medication. While orlistat is effective when it works well, only 37% of people taking it lost at least 5% of their starting weight after 12 weeks in clinical trials. Your doctor is likely to stop treatment after 12 weeks if you’ve not lost 5% of your starting weight.

Side effects can happen at any time while taking orlistat, but they’re most common in the first 3 months of treatment. This is the case with most weight loss treatments while your body adapts to the medication.

The most common side effects in the first month of taking orlistat are:

• oily or fatty stools
• an increased number of bowel movements
• urgent need to have a bowel movement
• oily discharge from the rectum
• gas with oily spotting
• difficulty controlling bowel movements

Most of these side effects are caused by the undigested fats passing through your system. They usually get better on their own, but if they get worse, or you’re finding them unmanageable, you should speak to your doctor.

Managing side effects

For the most part, you can manage the side effects of orlistat at home and reduce your likelihood of getting them by sticking to an appropriate low-fat diet. This means there’s less undigested fat going through your body, which is likely to cause these side effects alongside the medication.

➤ Learn more about an appropriate orlistat diet plan and how it can help you achieve safe and steady weight loss results.

Orlistat isn’t the only weight loss treatment available. It’s important to look at all the options before starting a weight loss journey so you can consider what best suits your needs. You may also want to change treatment if yours isn’t working as expected. Either way, your doctor will support you in making sure you’re on the right medication for your circumstances

Orlistat vs Mounjaro

Mounjaro is a weight loss injection that works very differently from orlistat. While orlistat changes how your body processes fats, Mounjaro reduces your appetite and delays the emptying of your stomach. When you take Mounjaro, you feel fuller from less food, and you feel fuller for longer. This makes it easier to stick to a 600-calorie deficit than it would be without taking it, so you lose more weight.

Mounjaro has been proven to help people lose up to 22.5% of their weight on the maximum 15mg tirzepatide dose over 72 weeks. That’s compared to a loss of 2.4% for those taking a placebo. Mounjaro is taken once a week with your injectable pen and the dose needs to be ‘titrated’ following a Mounjaro dosage schedule. This means you need to slowly increase your dose over time to avoid side effects while your body adapts to the medication. Whether you choose orlistat or Mounjaro will depend on things like whether you’d rather take a tablet or inject yourself, how much weight you want to lose, your budget, and your suitability for the medication. Orlistat is generally cheaper although Mounjaro has been proven to help more people lose weight.

Orlistat vs Wegovy

Wegovy works in the same way as Mounjaro by making you feel fuller for longer from less food. Again, this is different from orlistat, but it’s been proven to be effective, with patients losing up to 15% of their weight after 68 weeks on the maintenance dose of 2.4mg. Wegovy is (like Mounjaro) administered weekly, making it easier to remember than taking tablets after every meal.

However, you will still need to inject Wegovy and slowly titrate your Wegovy dose to make sure you don’t get too many side effects. You can also stay on a lower dose if you’re still getting good results and your side effects are more manageable or go away on a lower dose.

Orlistat vs Saxenda

Saxenda is a weight loss injection you take once a day. It’s been shown to help people lose around 8% of their body weight after 56 weeks on the 3mg maintenance dose. Saxenda works like Mounjaro and Wegovy by making you feel fuller from less food. Unlike Mounjaro and Wegovy, though, it must be taken daily.

Saxenda has been out of stock for a while, as manufacturers focus on weight loss injections like Wegovy and Mounjaro which only need to be taken once a week instead of every day, and have shown more promising results in clinical trials. We aren’t sure when Saxenda will be back in stock but there is a generic liraglutide injection coming to the UK.

Orlistat vs Mysimba

Mysimba is another weight loss tablet making it similar to orlistat in how it's taken. It works differently though, by affecting the part of your brain responsible for making you feel hungry and curbing your appetite instead of changing how your body absorbs fat.

You take it following a titrating dose schedule to a maximum daily dose of 2 tablets, twice a day, and you must follow a healthy diet plan and exercise regime to get the best results. Most people tend to lose around 8.1% of their body weight after 56 weeks of treatment with Mysimba.

Generally, most people expect to lose 1 to 2lbs per week (4 to 8lbs in the first 4 weeks) throughout their treatment with orlistat and in 3 months 37% of people will lose 5% of their weight. You can improve your chances of success with orlistat by following a diet plan that includes healthy, balanced meals, reducing your fat intake, and exercising.

This depends on the person, as some people notice results within a few weeks of taking orlistat and following their diet and exercise plan, while for some others it can take a little longer. That’s why your doctor will wait until 12 weeks after starting treatment to check you’ve lost at least 5% of your starting weight, so don’t worry if your progress is slow at first. It’s best to lose weight at a steady rate as this is more sustainable in the long term.

Are there any long-term studies on orlistat's effectiveness?

Studies show that out of the 37% of participants who lost 5% of their starting weight after 12 weeks, 49% of them went on to lose 10% or more after 1 year. Orlistat can be taken long-term and your doctor will decide whether it’s best to continue treatment after checking in on your weight at week 12.

Is orlistat safe long term?

As orlistat generally has very tolerable side effects and no significant drug toxicity, it is considered safe and effective for long-term weight management. However, in most cases, orlistat will not be prescribed long-term if you have not lost at least 5% of your starting body weight in 3 months of taking it.

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