How Mysimba Works for Weight Loss
Mysimba is a weight loss medication that can make a big difference to your BMI, but how does it work? Our team explains treatment in detail
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This content was reviewed and approved for its accuracy on 31/03/2022 by Professor Frank Joseph

Photograph of Professor Frank Joseph, weight loss expert for myBMI

How Mysimba Works for Weight Loss


Mysimba is a weight loss medication that’s been around for a few years now, introducing interesting new ideas to the theory of weight management treatments.

 

Like most weight management medications, it’s only available on prescription and will only be provided to people who have a BMI of 30 or above.

 

If you’re struggling with obesity and are finding it difficult to stick to a diet and exercise plan, Mysimba could help make things a little easier for you and help you on your way to a healthy weight.

 

So how does it do all this? Let’s find out together.

 

 

What is Mysimba?

 

Mysimba is the brand name of a weight-loss treatment that uses the active ingredients Naltrexone Hydrochloride and Bupropion Hydrochloride.

 

When you start treatment you’ll take one tablet a day before working up to 2 doses of 2 tablets every day, making this treatment an attractive alternative to the likes of Saxenda and Wegovy for those who hate needles.

 

So what’s going on in your system when you take Mysimba?

 

The answer lies in how the active ingredients work together, let’s have a look at both of them in turn and get a better idea of what they do and how they could help you lose weight.

 

 

What is Naltrexone?


Naltrexone, or Naltrexone Hydrochloride, is the first active ingredient in Mysimba and it’s also used in another medication — Adepend.

 

It was first developed as a treatment to help people stop taking opioid drugs, reducing their withdrawal symptoms and cravings.

 

The big benefit of Naltrexone is that it isn’t addictive in itself, essential when someone is already struggling with dependency.

 

So how does this medication work for weight loss?

 

Hold that thought, we’ll explain it all, but first, let’s learn a little more about the other active ingredient in Mysimba.

 

 

What is Bupropion?


Bupropion hydrochloride is active ingredient number two and like Naltrexone, it’s primarily used in another medication — Zyban.

 

Zyban is a medication given to people who want to quit smoking but need a little help with the cravings.

 

Bupropion works at its best when the patient is completely dedicated to quitting smoking, so it will only be prescribed to those who have a plan to quit in mind and need a little help to make it happen.

 

Noticing a pattern? Both of the medications in Mysimba are made to help people who are suffering from addiction issues in one way or another without causing further dependency.

 

Now we know more about how they work, we can start to think about how they factor into a weight loss plan.

 

 

How does Mysimba work?


Mysimba uses its two active ingredients to help those with a BMI of 30 or above reach a healthy weight when combined with diet and lifestyle changes.

 

As we’ve just seen, these ingredients are particularly effective when used to help people who want to quit addictive substances — which is exactly why they can work for weight loss.

 

If you’ve ever experienced food cravings or tried to cut down on junk food just to bounce back into a binge then you’ll know that for some people, food can feel almost addictive in itself.

 

As we need food to live, you can’t cut it out completely as you can with addictive substances like nicotine, but the way Mysimba is thought to work in the brain could make it easier for you to kick any bad habits you have around eating.

 

This should make it easier for you to stick to a calorie-controlled diet and start losing weight consistently.

 

 

Does Mysimba work for weight loss?

 

Mysimba can work for weight loss, in fact, you should lose at least 5% of your starting body weight by the time you have been taking it for 16 weeks.

 

This means that if you started with a weight of 300lbs, you should have lost 15lbs by the time you’ve gone through 16 weeks of treatment, bringing you down to 285lbs.

 

If you haven’t lost 5% of your starting weight in 16 weeks then Mysimba may not be the best treatment for you and your prescriber may end the treatment altogether.

 

Don’t be too concerned about this though, there are always other treatments you can try, including Saxenda, Wegovy, and Orlistat which may be a better fit for you.

 

 

Is this treatment effective?


Yes, Mysimba can be effective at helping you to lose weight but it won’t work on its own.

 

Mysimba is a helping hand that can make it easier for you to break bad habits around your diet, not an absolute cure for obesity.

 

You’ll need to consistently be at a calorie deficit to lose weight, which means eating fewer calories than your body needs for energy, so yes, you will need to change your diet to lose weight.

 

Mysimba will help to make these changes a little easier and help you to stick to them for a prolonged period of time, giving you time to reach a healthy weight and BMI.

 

 

How long does it take to work?


As we’ve previously mentioned, you should lose at least 5% of your starting weight by the 16-week mark if Mysimba is the right treatment for you.

 

Of course, the amount of time it will take for you to reach a healthy weight will be different from person to person, as you will need to consider how much weight you would need to lose and what percentage of your starting weight that would make up.

 

For example, if you were 5’8” (173cm) tall and weighed 240lbs, you would need to lose around 80lbs to reach a healthy BMI of 160lbs.

 

This means you would need to lose about 33% of your starting weight to reach a healthy weight bracket.

 

With that in mind, if you consider a slow loss of around 1lb a week you can make a good guess of how long it would take for you to reach your weight loss goals with Mysimba.

 

 

Now we know a lot more about how Mysimba works and how long it could take for you to reach your weight loss goals.

 

Still have questions? Why not check out some of our other guides and advice pieces that our readers love.

 

Here are a couple of our favourites to get you started.

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