Our Pricing

What Are Mysimba Tablets and How Do They Work for Weight Loss?

Mysimba tablets are a prescription weight loss medication combining naltrexone and bupropion, designed to help adults with obesity achieve clinically significant weight reduction when used alongside a reduced-calorie diet and increased physical activity. Available from Cured Pharmacy at £83.00 mysimba tablets work by targeting areas of the brain that regulate appetite and cravings, offering a different mechanism of action compared to injectable GLP-1 treatments. This dual-action oral medication has been licensed by the MHRA for weight management in patients with a BMI of 30 kg/m² or above, or 27 kg/m² with weight-related comorbidities.

How Mysimba Tablets Work: Naltrexone-Bupropion Mechanism

Mysimba tablets contain two active ingredients: naltrexone hydrochloride (8mg) and bupropion hydrochloride (90mg) in each film-coated tablet. This combination works synergistically on the hypothalamus and mesolimbic reward system to reduce hunger and control cravings [1]. Naltrexone, traditionally used for alcohol and opioid dependence, blocks opioid receptors, while bupropion, an antidepressant and smoking cessation aid, inhibits the reuptake of dopamine and noradrenaline.

The dual mechanism of mysimba tablets helps patients feel fuller sooner and reduces the rewarding aspects of eating, particularly for high-calorie foods. Clinical trials demonstrated that this neurochemical approach can lead to average weight loss of 5-10% of initial body weight over 56 weeks when combined with lifestyle modifications [2]. The medication requires gradual dose escalation over four weeks to minimise side effects, reaching a maintenance dose of two tablets twice daily.

Unlike fat absorption inhibitors such as orlistat, mysimba tablets work centrally in the brain rather than in the digestive system. This makes them particularly suitable for patients whose weight gain is driven by appetite dysregulation, emotional eating, or food cravings rather than purely dietary fat intake.

Mysimba Tablets Dosage and Treatment Schedule

The dosing schedule for mysimba tablets follows a strict escalation protocol to improve tolerability. Week one begins with one tablet each morning, increasing to one tablet twice daily in week two, then two tablets in the morning and one in the evening during week three, before reaching the full maintenance dose of two tablets twice daily from week four onwards [3].

Patients should take mysimba tablets with food to reduce the risk of nausea, one of the most common initial side effects. The tablets must be swallowed whole and should not be cut, crushed, or chewed, as this affects the modified-release formulation. Treatment response is typically assessed at 16 weeks—if a patient has not lost at least 5% of their initial body weight by this point, discontinuation should be considered as the medication may not be effective for that individual.

Maximum treatment duration is not specified, but ongoing clinical review is essential. Mysimba tablets require prescription from a UK-registered prescriber following a comprehensive clinical assessment that considers medical history, current medications, and contraindications including uncontrolled hypertension, seizure disorders, and eating disorders.

Who Can Take Mysimba Tablets?

Mysimba tablets are licensed for adults aged 18 and over with an initial BMI of 30 kg/m² or greater (obese), or 27 kg/m² or greater (overweight) in the presence of weight-related comorbidities such as type 2 diabetes, dyslipidaemia, or controlled hypertension. The medication is not suitable for everyone—contraindications include pregnancy, breastfeeding, uncontrolled hypertension (≥145/90 mmHg), seizure disorders, current or prior diagnosis of bulimia or anorexia nervosa, bipolar disorder, and concurrent use of MAO inhibitors [4].

Patients taking certain medications including other bupropion products, opioid analgesics, or medications that lower the seizure threshold require careful evaluation before starting mysimba tablets. A thorough online consultation with Cured Pharmacy's UK-registered prescribers ensures safety and appropriateness before treatment initiation.

Clinical Evidence for Mysimba Tablets Effectiveness

The efficacy of mysimba tablets has been established through four pivotal phase 3 trials known as the COR (Contrave Obesity Research) programme, involving over 4,500 patients [2]. These randomised, double-blind, placebo-controlled studies demonstrated that patients taking naltrexone-bupropion achieved significantly greater weight loss compared to placebo when combined with diet and exercise interventions.

In the COR-I trial, 48% of patients on mysimba tablets achieved at least 5% weight loss at 56 weeks, compared to 17% on placebo. Furthermore, 25% of mysimba patients achieved ≥10% weight loss versus just 7% in the placebo group [2]. The COR-Diabetes study specifically examined patients with type 2 diabetes, showing average weight loss of 5% alongside improvements in glycaemic control, though the medication is not licensed as a diabetes treatment.

Long-term data from the COR-II trial, which included a two-year extension phase, demonstrated sustained weight loss maintenance in patients who continued treatment. However, as with all weight management medications, weight regain typically occurs upon discontinuation if lifestyle changes are not maintained [1]. These trials provide robust evidence supporting mysimba tablets as an effective pharmacological adjunct to comprehensive weight management programmes.

Expected Weight Loss Timeline

Patients taking mysimba tablets typically begin noticing weight loss within the first month of treatment, with more significant results becoming apparent by 16 weeks. Clinical trials showed that most weight loss occurred within the first 36 weeks of treatment, with weight stabilisation thereafter in responders [2]. Individual results vary considerably based on adherence to the medication, dietary modifications, physical activity levels, and metabolic factors.

The 16-week checkpoint is clinically significant—guidelines recommend discontinuing mysimba tablets if less than 5% weight loss has been achieved by this point, as continued treatment is unlikely to produce meaningful results. Patients who do respond well may continue treatment for extended periods under ongoing medical supervision, with regular review of cardiovascular risk factors and blood pressure monitoring.

Mysimba Tablets Side Effects and Safety Considerations

The most frequently reported side effects of mysimba tablets include nausea (occurring in approximately 30% of patients), constipation, headache, vomiting, dizziness, insomnia, dry mouth, and diarrhoea [3]. These effects are generally most pronounced during the dose escalation phase and often diminish with continued use. Taking the medication with food and following the gradual titration schedule significantly reduces gastrointestinal symptoms.

More serious but less common risks include increased blood pressure and heart rate, which necessitate regular monitoring throughout treatment. Mysimba tablets carry a boxed warning in some jurisdictions regarding neuropsychiatric effects, including mood changes, depression, and suicidal ideation, related to the bupropion component [4]. Patients with a history of depression or other psychiatric conditions require particularly careful assessment and monitoring.

Seizure risk is a critical consideration—bupropion lowers the seizure threshold in a dose-dependent manner. The risk is approximately 0.4% at the recommended dose but increases substantially with higher doses or in patients with predisposing factors [4]. Alcohol consumption should be minimised during treatment with mysimba tablets, and patients should be advised to stop taking the medication and seek immediate medical attention if they experience a seizure.

Buying Mysimba Tablets Online from Cured Pharmacy

Cured Pharmacy offers mysimba tablets at £83.00 representing competitive UK pricing for this prescription weight loss medication. Our streamlined online consultation process, completed in under three minutes, connects you with UK-registered prescribers who assess your suitability for treatment based on comprehensive medical and lifestyle information. All mysimba tablets supplied are genuine UK-licensed medications sourced through regulated pharmaceutical channels.

The ordering process is transparent and discreet—prices are displayed upfront before consultation, eliminating surprise costs. Following prescriber approval, mysimba tablets are dispensed by our GPhC-registered pharmacy (registration number 9012511) under the supervision of Superintendent Pharmacist Tarun Kumar (GPhC 2233073). Discreet packaging ensures privacy, and our clinical team remains available for ongoing support throughout your treatment journey.

As a prescription-only medicine, mysimba tablets cannot be purchased without a valid prescription from a UK-registered healthcare professional. Our clinical assessment ensures the medication is safe and appropriate for your individual circumstances, considering your medical history, current medications, and weight loss goals. This regulatory framework protects patient safety while providing convenient access to effective weight management treatments.

Prescription Requirements and Online Consultation

The online consultation for mysimba tablets covers essential medical information including current weight and height, previous weight loss attempts, existing medical conditions (particularly cardiovascular, neurological, and psychiatric), current medications, and lifestyle factors. Accurate completion of this assessment is crucial—providing incomplete or inaccurate information may result in inappropriate prescribing or treatment delays.

UK prescribers reviewing your consultation will determine whether mysimba tablets are suitable based on MHRA licensing criteria and clinical guidelines. If the medication is deemed inappropriate, alternative treatments may be recommended, or you may be advised to consult your GP for further evaluation. This clinical governance ensures patient safety remains paramount while providing accessible weight management support.

Mysimba Tablets Compared to Other Weight Loss Treatments

When considering mysimba tablets versus other weight loss medications available in the UK, several factors differentiate treatment options. Unlike GLP-1 receptor agonists such as Wegovy or Saxenda, which are injectable medications that slow gastric emptying and enhance satiety through gut hormone pathways, mysimba tablets work centrally on brain appetite centres and are taken orally. This makes them preferable for patients who wish to avoid injections or have contraindications to GLP-1 therapies.

Compared to orlistat (Xenical, Alli), which blocks approximately 30% of dietary fat absorption in the intestines, mysimba tablets offer a different mechanism targeting appetite and cravings rather than nutrient absorption [1]. Orlistat is associated with gastrointestinal side effects related to unabsorbed fat, while mysimba tablets more commonly cause neurological and psychiatric effects. The choice between these medications depends on individual patient factors, preferences, side effect profiles, and clinical assessment.

Clinical trial data suggests that mysimba tablets produce average weight loss comparable to or slightly greater than orlistat, though generally less than the newer GLP-1 receptor agonists [2]. However, the oral administration route, different mechanism of action, and suitability for patients with specific contraindications to other treatments make mysimba tablets a valuable option in the weight management medication portfolio. Combination with comprehensive lifestyle interventions remains essential regardless of which pharmacological treatment is selected.

Scientific References

1. Greenway, F. L., Fujioka, K., Plodkowski, R. A., Mudaliar, S., Guttadauria, M., Erickson, J., Kim, D. D., & Dunayevich, E. (2010). Effect of naltrexone plus bupropion on weight loss in overweight and obese adults (COR-I): a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial. The Lancet, 376(9741), 595-605. Retrieved 3 August 2026.
2. Apovian, C. M., Aronne, L., Rubino, D., Still, C., Wyatt, H., Burns, C., Kim, D., & Dunayevich, E. (2013). A randomized, phase 3 trial of naltrexone SR/bupropion SR on weight and obesity-related risk factors (COR-II). Obesity, 21(5), 935-943. Retrieved 3 August 2026.
3. Electronic Medicines Compendium. (2023). Mysimba 8 mg/90 mg prolonged-release tablets - Summary of Product Characteristics. Medicines.org.uk. Retrieved 3 August 2026.
4. Yanovski, S. Z., & Yanovski, J. A. (2014). Long-term drug treatment for obesity: a systematic and clinical review. JAMA, 311(1), 74-86. Retrieved 3 August 2026.

Information on this page is for educational purposes only and is not medical advice. All prescription treatments require clinical assessment by a UK-registered prescriber. Always consult a qualified healthcare professional before starting any new medication.

At Cured Pharmacy, we make it personal

Every treatment is reviewed by our UK-registered clinical team, dedicated to safe, personalised care.