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Mysimba is an oral weight loss medication that uses the active ingredients naltrexone and bupropion. It is thought to help reduce food cravings, making it easier for you to stick to a weight management plan.

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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 Mysimba for Weight Loss

If you’re searching for the perfect weight loss medication for you, you may want to ask our prescribers about myBMI’s Daily Combo treatment plan.

This plan provides weight loss tablets called Mysimba, and will include help to navigate through dosage increases and support if you experience any side effects as your body gets used to the treatment.

But what exactly is Mysimba? Let’s take a closer look at this medication together and find out everything you need to know to make an informed decision about your treatment.

What is in Mysimba?

Mysimba tablets contain two active ingredients, the first is Naltrexone and the second is Bupropion.

These ingredients work together to form an effective weight loss treatment that works differently from other weight loss tablets on the market.

Each Mysimba tablet contains 8mg of Naltrexone Hydrochloride and 90mg of Bupropion Hydrochloride.

Here’s some more information about these ingredients and how they’ll help you lose weight.

Naltrexone Hydrochloride

Now I’ll bet there are a few of you out there scratching your heads right now, thinking “wait, isn’t Naltrexone used for addiction?”

You’re right, Naltrexone is used to help people recover from addictions to alcohol or drugs (specifically, opiates), but it can also be used for weight loss when it’s combined with Bupropion.

This is why prescribers recommend that you avoid drinking alcohol as much as you possibly can while you’re taking Mysimba, and why you can’t take it alongside painkillers like codeine.

Bupropion Hydrochloride

Bupropion Hydrochloride is another medication you may be familiar with, as it’s used in a medication called Zyban to help people quit smoking.

At the moment, it’s only licensed for smoking cessation in the UK, but it’s licensed in the US as an antidepressant, where it’s also known as Wellbutrin.

This is why you’ll be asked whether you take antidepressants during your Mysimba consultation with myBMI, our professionals will need to be sure that anything we prescribe won’t interact with your regular medication.

How does Mysimba work?

Now we know a bit more about Naltrexone and Bupropion you’re probably wondering how these two medications can help you lose weight.

Well, it turns out that the way these ingredients work for addiction is the key to the way Mysimba works for weight loss.

This medication is thought to affect the part of your brain that controls your food intake as well as the part that causes pleasure when you eat.

So essentially, Mysimba is thought to help reduce your cravings and change the way you feel about food in general by making it less pleasurable to eat.

These changes make it easier for you to stick to a calorie-controlled diet, and therefore make it easier for you to lose weight.

What dose of Mysimba should I take?

The dose of Mysimba you should be taking will depend on what stage of your treatment you’re up to.

When you first start to take this treatment you’ll take one Mysimba tablet a day for a week, after this, you’ll usually increase your dose by one tablet a week until you’re taking a maximum of four tablets every day.

This gradual increase in dose is called titration and it will help your body to get used to the treatment and reduce your risk of side effects.

Titration Path

During the first 4 weeks of your treatment you’ll gradually increase your dose of Mysimba week by week.

The Starter stage of our plan provides enough tablets for this 4 week period and is here to help you start taking your medication successfully and increase your dose safely.

You’ll usually start off taking one Mysimba tablet every morning, then you’ll usually increase to two tablets a day during week two, then three tablets a day during week three, until finally increasing to two tablets twice a day for a total of four every day.

When you reach week 4 you’ll be taking the highest possible dose of Mysimba, with two tablets in the morning and two in the evening for a total dose of 32/360mg a day.

You’ll usually continue on this dose until you decide to end your treatment, which is why this part of your treatment plan is named “Sustain”.

When you reach this stage of treatment for the first time, you may not have seen much movement on the scales, but by the time you’ve been taking Mysimba for 16 weeks you should have lost at least 5% of your starting weight, if not more.

From this point on, you’ll continue on this dose while you work to maintain your weight loss.

How long will it take for me to see weight loss results?

You’ll usually see progress within 16 weeks of starting Mysimba, which is when your healthcare team will evaluate your progress with you.

If this treatment is working for you, you’ll lose at least 5% of your starting body weight within these 16 weeks.

This means that if you weigh 240 pounds at the start of your treatment, you should lose at least 12 pounds before your progress evaluation.

If you haven’t lost at least 5% of your starting weight within this time, this treatment probably isn’t right for you and your prescriber will end your treatment.

They may recommend other ways to lose weight, including different weight loss medications that may be a better fit for you.

Do these tablets have side effects?

Like all medications, Mysimba can have side effects, although not everyone will experience them.

By going through the titration process and increasing your dosage gradually, you’ll typically experience fewer side effects as your body will find it easier to get used to the treatment.

There are some severe side effects you can experience while taking this medication.

If any of these happen to you, you should seek immediate medical assistance.

This may be from your GP or pharmacist, a local walk-in centre, or the A&E department at your nearest hospital, if necessary. These severe side effects include:

  • Suicidal thoughts and depression
  • Fits or seizures, especially in those who are at higher risk of fits
  • Erythema multiforme and Stevens Johnson Syndrome — severe skin conditions
  • Rhabdomyolysis, causing muscular pain or problems
  • Lupus skin rash or worsening of lupus symptoms
  • Serotonin syndrome

The other common side effects of Mysimba include:

  • Feeling or being sick
  • Constipation
  • Headaches
  • Anxiety
  • Dizziness
  • Feeling shaky, tremors
  • Difficulty sleeping, insomnia
  • Changes to the taste of food, dry mouth
  • Difficulty concentrating
  • Tiredness, drowsiness, lack of energy
  • Ringing in the ears, tinnitus
  • Fast or irregular heartbeat
  • Hot flush
  • Increased blood pressure
  • Pain in the abdomen or upper part of the abdomen
  • Excessive sweating
  • Rashes, itching
  • Hair loss
  • Irritability
  • Feeling jittery

Which is better, Mysimba or Saxenda?

Saxenda is another weight loss medication that has become much more popular in recent years.

It uses an ingredient called Liraglutide to affect your hormones and reduce your appetite and cravings.

Although this sounds similar to Mysimba, it actually affects the hormones in your pancreas, while Mysimba is thought to affect the brain.

Another key difference is how you take your medication — Saxenda is an injectable medication whereas Mysimba comes as tablets.

You’ll take both medications every day.

The final important difference is how quickly these medications work, with Saxenda usually taking 12 weeks on the highest possible dose for you to lose at least 5% of your body weight, while Mysimba does this in 16 weeks.

At the end of the day, which medication is better will depend entirely on you, your lifestyle, and how your body reacts to weight loss treatments.

If you’re looking for more information as you’re trying to make your choice you should speak to your local healthcare team and read the articles in our advice section while you wait for your appointment.

We’ve written a host of different articles about Saxenda and other weight loss medications, so you can swot up on your options before making your choice.

How much does treatment cost?

Mysimba is a prescription-only medication, so you can’t buy it directly.   Instead, you’ll need a prescription from an appropriate medical professional.

Many people find that their GP won’t prescribe weight loss medications, as they have a lot of different boxes they need to check before they can write a prescription of weight loss drugs.

This is where myBMI really shines.

When you come to us, you’ll pay a flat fee of £199* for your consultation with our prescribers.

This fee will also cover the cost of your treatment (which could be one of a range of weight loss medications), delivery from our dispensing pharmacy, and any supporting treatments you may need to help you manage side effects like nausea and headaches.

*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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