Mysimba Prolonged Release Tablets

Based on 26 reviews

Available in 112 and 224 tablets

  • Weight loss medication
  • Helps reduce food cravings
  • For those with a BMI of 30 or over
  • Always read the patient information leaflet before use.
Pack Size
112 Tablets
224 Tablets
The treatment is inclusive of consultation, private prescription & medicine delivery
How we are regulated
Our Consultations
Let us explain how it works
select consultation
Step 1
Choose a Condition
Select your condition
complete detail
Step 2
Complete a consultation
Answer questions designed by our healthcare professionals, so we can determine the relavant treatment for you.
suggested treatment
Step 3
Choose a Treatment
We will determine any relevant treatments that we can provide to treat your conditions
fast delivery
Step 4
Fast and discreet Delivery
We will issue the prescription and treatment in one cost and have your treatment sent out to you fast and discreet by the royalmail post
Laura Henderson - Medical Content Writer
Laura Henderson
Medical Content Writer
James O'Loan - CEO & Superintendent Pharmacist
James O'Loan
CEO & Superintendent Pharmacist

Buy Mysimba weight loss tablets

Mysimba tablets are a weight-loss treatment which can help you to lose weight by reducing your appetite and food cravings. When paired with a low-calorie diet and regular exercise programme, these tablets may help you to change how you lose weight by making you feel less hungry. If you’re an adult with a BMI of 30 or above, Mysimba could be the right choice of treatment to help you along your weight loss journey.


How Mysimba works

Each Mysimba tablet contains two active ingredients, 8mg of Naltrexone Hydrochloride and 90mg of Bupropion Hydrochloride. These ingredients work together on different areas of your brain to help reduce your appetite and reduce food cravings. By suppressing your appetite, these tablets help you to eat less food and consume fewer calories, which can help you to lose weight. When combined with a low-calorie diet and regular exercise, this treatment may help you to change how you feel about food, helping you to form good habits which may lead to you losing weight and keeping it off.



Your prescriber will decide the dose of Mysimba you should be taking and you should always follow their instructions carefully. However, they will usually recommend that you take these tablets in the following doses, gradually increasing the dose week by week until week 4:


Week 1 One tablet a day, taken in the morning
Week 2 Two tablets a day, one in the morning and one in the evening
Week 3 Three tablets a day, two in the morning and one in the evening
Week 4 and onward Four tablets a day, two in the morning and two in the evening. This is the maximum dose you should take


You should take your tablets with food and swallow them whole. After 16 weeks, your prescriber will assess whether you should continue taking Mysimba. If you have not lost at least 5% of your starting body weight after this time your treatment may be stopped.


Side effects

Like all medications, Mysimba tablets can have side effects, although you may not experience them.

Other common side effects you may experience include:

  • Feeling or being sick

  • Constipation

  • Headaches

  • Anxiety

  • Dizziness, feeling like you’re “spinning”, vertigo

  • Feeling shaky, tremors

  • Difficulty sleeping, insomnia

  • Changes in how your food tastes, dry mouth

  • Difficulty concentrating

  • Feeling tired and sleepy, drowsiness, lack of energy, lethargy, fatigue

  • Ringing in the ears, tinnitus

  • Fast or irregular heartbeat

  • Hot flushes

  • Increased blood pressure, which may be severe

  • Pain in your abdomen or upper abdomen

  • Excessive sweating

  • Rash, itching, pruritus

  • Hair loss, alopecia

  • Irritability

  • Feeling jittery

For a complete list of potential side effects you may experience while taking this medication, please see the patient information leaflet included with your product. If you experience these or any other side effects while taking this product, speak to your doctor or pharmacist. For more information about reporting the side effects of medication, please see the MHRA’s Yellow Card Scheme.


Serious side effects

If you experience any of the following serious side effects you should seek immediate medical attention, either from your doctor or A&E if necessary:

  • Suicidal thoughts, depression, thoughts about harming yourself, and other distressing thoughts

  • Fits or seizures, loss of consciousness

  • Symptoms of erythema multiforme and Stevens-Johnson Syndrome, e.g. red, itchy spots which start on your limbs, severe blisters, bleeding in the lips, eyes, mouth, nose, and genitals

  • Symptoms of rhabdomyolysis, e.g. severe muscle cramps, muscle pain, muscle weakness

  • Symptoms of a severe allergic reaction, e.g. difficulty breathing or swallowing, pain in the joints or muscles, rash, itching, hives, dizziness, fever, swelling of the face, mouth, tongue, or throat



Mysimba tablets are not suitable for use in children under the age of 18. If you are older than 65 you should speak to your doctor before using this product, as it may not be suitable for you. These tablets are not recommended for those over the age of 75. Do not take this product if you are allergic to naltrexone, bupropion, or any of the other listed ingredients. You should not take these tablets if you:

  • Have an abnormally high blood pressure which is not controlled using medication

  • Have a condition which causes fits or seizures, or have a history of fits

  • Have a brain tumour

  • Are an unusually heavy drinker and have just stopped drinking alcohol or are planning to stop while taking Mysimba

  • Have recently stopped taking sedatives or medications used to treat anxiety or are planning to stop while taking Mysimba. This especially applies if you are taking benzodiazepines

  • Have or have ever had a bipolar disorder or extreme mood swings

  • Are using any other medications which contain naltrexone or bupropion

  • Have or have ever had an eating disorder, e.g. anorexia nervosa, bulimia

  • Are currently dependent on chronic opiates or opiate antagonists such as methadone, or are going through acute withdrawal, also known as going cold turkey

  • Are taking medicines for depression or Parkinson’s disease called MAOIs or have taken them within the last 2 weeks

  • Have severe liver disease

  • Have endstage kidney disease

Speak to your prescriber, GP, or pharmacist before taking this product if you:

  • Feel depressed, contemplate suicide, have a history of attempting suicide, or have any other mental health problems

  • Have had a serious head injury or head trauma

  • Regularly drink alcohol

  • Regularly use sleeping medicines

  • Are dependent on or addicted to cocaine or other stimulants

  • Have diabetes and use insulin and other medicines which may cause low blood sugar levels

  • Are taking medicines which may increase the risk of fits

  • Have high blood pressure

  • Have uncontrolled coronary artery disease with symptoms like chest pain or a recent heart attack

  • Have or have ever had a condition affecting the circulation of blood in your brain

  • Have any liver problems

  • Have any kidney problems

  • Have a history of mania causing unusual behaviour as well as feelings of elation or over-excitement

  • Have an intolerance to some sugars, as these tablets contain lactose


Other medications

If you’re taking any other medication you should tell your prescriber about them during your first consultation. Some medications should not be taken together and your prescriber will need this information to help them decide whether Mysimba is right for you. You should not take these tablets if you are already taking:

  • Monoamine oxidase inhibitors (MAOIs), which are used for depression or Parkinson’s disease, e.g. phenelzine, selegiline, rasagiline. You will not be able to take Mysimba if you have taken an MAOI within the last 14 days

  • Opiates or medicines which contain opiates, e.g. codeine, dextromethorphan, methadone, morphine, paregoric. You must have stopped taking any opiates for at least 7 - 10 days before you will be able to take Mysimba

Your prescriber will also need to know if you are already taking:

  • Medicines which can increase your risk of fits when taken with naltrexone or bupropion, e.g. medicines for depression or mental health problems, steroids, medicines to prevent malaria, quinolone antibiotics, tramadol, theophylline, antihistamines which make you sleepy (e.g. chlorphenamine), insulin or other medicines used to lower your blood sugar, medicines to help you sleep

  • Medicines used to treat depression or other mental health problems, e.g. desipramine, venlafaxine, imipramine, paroxetine, citalopram, risperidone, haloperidol, thioridazine

  • Medicines used for high blood pressure, e.g. beta-blockers like metoprolol, antihypertensives like clonidine

  • Medicines used for irregular heart rhythm, e.g. propafenone, flecainide

  • Medicines used to treat cancer, e.g. cyclophosphamide, ifosphamide, tamoxifen

  • Medicines for Parkinson’s disease, e.g. levodopa, amantadine, orphenadrine

  • Ticlopidine or clopidogrel, which are used for heart disease or stroke

  • Medicines used for HIV or AIDS, e.g. efavirenz, ritonavir

  • Medicines used for epilepsy, e.g. valproate, carbamazepine, phenytoin, phenobarbital


Pregnancy and breastfeeding

If you’re pregnant or breastfeeding you should not take Mysimba. If you’re worried about weight gain or the effects that obesity could have on your pregnancy, ask your doctor, pharmacist, or healthcare team for advice. They’ll be more than happy to provide safe options that could help you to lose or manage your weight without causing a risk to your baby. For example, they may suggest a diet or exercise programme that’s safe to do during your pregnancy and will help your growing child get the nutrients they need from you.



Your prescriber will usually suggest that you don’t drink alcohol while you’re taking Mysimba. Alcohol can increase your chances of experiencing fits, seizures or mental disorder events while using this treatment. These tablets can also reduce your tolerance for alcohol, which could make you more vulnerable to the effects of drinking. However, if you drink a lot at the moment you shouldn’t stop drinking suddenly, as this can also increase your risk of having a fit. Reduce your alcohol intake gradually and ask your GP for help if you need it.



You may feel dizzy or sleepy after taking Mysimba weight loss tablets, and this can affect your concentration and your ability to drive. If you experience this or any other symptoms which could make it difficult for you to concentrate or react properly you should not attempt to drive or use any tools or machinery until the effects have passed and you are sure you are safe to do so. If this treatment causes fits, fainting, or muscle weakness you should not attempt to drive and should speak to your doctor right away.


Important information

This product is a medicine; make sure to speak to your doctor or Chemist4U pharmacist before taking this product if you have an underlying medical problem or are taking any other medicine or complementary therapy. If your symptoms get worse or continue after taking this product, contact us or your doctor. For medical services in your area, please refer to

If you are pregnant, trying to become pregnant, or breastfeeding, speak to your doctor or our pharmacist before taking this product. If you suffer from any allergies, ask your doctor or our pharmacist if this medicine is right for you.

Store all medicines out of sight and reach of children.

Please read the included leaflet carefully before using this product.

Please contact your GP if appropriate regarding this product.



Store in a cool, dry place which is below 30 degrees C. Do not use this product if the expiry date printed on the original packaging has passed. Keep out of sight and reach of children.

Mysimba Prolonged Release Tablets Reviews

April 03, 2024
Lucky enough not to have any side effect.
By John Munford,
March 26, 2024
It works for me I've been taking half a full dose now for a little over four months. I have lost 12kg. 10kg more to go.
By Csaba Ervin,
September 19, 2023
Very effective way of weight lose , no experienced side effects
By Nathan Feary,
August 22, 2023
So far so good, 1 week into taking these. My cravings have reduced, making it easier to stick to a calorie restricted diet.
By Ella Higgins,
August 22, 2023
good for weight loss, lost 20lbs so far

Advice & Guides

Do weight loss pills really work?

When it comes to losing weight, people want to do it quickly. Lots of exercise, strict diet, and supplements, including weight loss pills, are usually taken in the hope that this will speed up the process.

Read More

Funding your weight loss treatment

  Whether you’ve decided upon your weight loss treatment or you’re still browsing the market, the question you might be asking is how you’ll pay for your treatment – is it funded by the NHS? Do you have to pay privately? What about if you have insurance? In this guide...
Read More
Frequently Asked Questions

Are Mysimba and Wellbutrin the same thing?

Wellbutrin is an antidepressant medication used in the UK to treat nicotine addiction and help you quit smoking.

It’s also used to treat major depressive disorder (MDD) and seasonal affective disorder (SAD) in other countries, although it is not currently licensed to be used for this in the UK.

The active ingredient in Wellbutrin is Bupropion, which is also used as an active ingredient in Mysimba, making these medicines very similar.

However, as Mysimba also contains a second active ingredient (Naltrexone) which is not included in Wellbutrin, these medications are not the same thing.

With that in mind, Wellbutrin should not be used for weight loss and should only be used as prescribed by a doctor to help you quit smoking.

Are Mysimba weight loss tablets right for me?

Mysimba tablets should only be taken by adults over the age of 18 who have a body mass index (BMI) of 30 and above, which would place them into the obese category.

However, you may also be able to take this treatment if your BMI is between 27 and 30 and you also have weight-related conditions, such as high blood pressure, type 2 diabetes, or high levels of fat in your blood.

Your BMI is calculated using your weight and your height and is a good indicator of whether or not you are at a healthy weight.

If you’re unsure what your BMI is, we’d recommend using the NHS’s BMI Calculator which will work it out for you and give you an indication of whether you may be able to use Mysimba for weight loss.

Do I need a prescription for this medication?

You do need a prescription for this medication in the UK.

Our healthcare professionals can provide prescriptions if they think this treatment would be right for you and your condition.

When you click the button which reads “Start Consultation” at the top of this page, you’ll see a short questionnaire set up by our healthcare team which is designed to help them understand your medical needs.

Just like an in-person consultation with your GP, our doctors will assess your answers to their questions and write a prescription for the treatment they think will be best for you.

You’ll then be able to pay for your medication and we’ll send it out to you quickly and in discreet packaging.

© 2024 Chemist4U. Innox Trading Ltd, 35-37 Greenhey Place, Skelmersdale, Lancashire, WN8 9SA, GB. All rights reserved. Registered and regulated UK pharmacy with the GPhC (registered premises 9011784). Registered in England No. 07262043 | VAT Registration No. GB140138454