Mysimba Tablets
Mysimba (naltrexone/bupropion) is an oral prescription medication for weight management in adults with obesity or overweight with weight-related conditions. This combination therapy is available through Chemist Doctor's regulated online service following a consultation with UK-licensed clinicians.
You must complete a short online consultation so that our prescriber can ensure that the treatment is suitable for you.
Assessment
Answer some questions about your health concerns & symptoms
Treatment
Connect with a clinician 100% online, no appointment needed
Delivery
Get your medication delivered directly, if prescribed
Table of Contents
What is Mysimba?
Mysimba (naltrexone/bupropion) is a prescription weight loss medication approved by the European Medicines Agency (EMA) for adults with obesity (BMI ≥30) or overweight (BMI ≥27) with weight-related comorbidities.
What Makes Mysimba Tablets Unique?
This dual-action medication combines:
- Naltrexone HCl (8mg) - opioid receptor antagonist
- Bupropion HCl (90mg) - dopamine/noradrenaline reuptake inhibitor
According to EMA research, this unique combination targets hypothalamic hunger regulation and mesolimbic reward pathways.
The UK Obesity Crisis
NHS Digital data shows:
| Category | Percentage |
|---|---|
| Obese Adults | 29% |
| Overweight Adults | 36% |
Understanding BMI Classification
Body Mass Index categories:
- Healthy: 18.5-24.9
- Overweight: 25-29.9
- Obese: ≥30
Calculate your BMI using the NHS BMI Calculator.
How Does Mysimba Work?
Mode of action:
- Reduces hunger signals in hypothalamus
- Decreases food craving through dopamine modulation
- Increases energy expenditure via noradrenergic activity
Clinical Effectiveness of Mysimba
- 5-10% body weight loss in 56 weeks
- 67% patients achieved ≥5% weight loss vs 23% placebo
Combining Diet & Exercise with Mysimba
Essential components for success:
- Calorie-controlled diet (NHS Eatwell Guide)
- 150 mins weekly moderate exercise
- Behavioural modification strategies
Tracking Your Weight Loss
Effective monitoring methods:
- Weekly weigh-ins
- Food diary apps (MyFitnessPal)
- Waist circumference measurements
Mysimba Dosage
Proper dosage escalation is critical for tolerability and effectiveness:
| Treatment Week | Dosage Schedule | Maximum Daily Dose |
|---|---|---|
| Week 1 | 1 tablet each morning | 8mg naltrexone/90mg bupropion |
| Week 2 | 1 AM + 1 PM tablet | 16mg/180mg |
| Week 3 | 2 AM + 1 PM tablet | 24mg/270mg |
| Week 4+ | 2 AM + 2 PM tablets | 32mg/360mg |
Administer with food to reduce nausea risk. Tablets must be swallowed whole - never crush or split.
Managing Missed Doses & Overdose Risks
Missed Dose Protocol:
If >4 hours until next dose: Skip missed dose
If <4 hours until next dose: Take immediately
Never double dose to compensate
Overdose Emergency Actions:
1. Contact NHS 111 immediately
2. Visit nearest A&E for seizures/tachycardia
3. Bring medication packaging
Mysimba Medication Interactions
Key contraindications per BNF guidelines:
- MAOIs: Risk of hypertensive crisis (minimum 14-day washout)
- Opioid Analgesics: Naltrexone blocks opioid effects
- SSRIs/SNRIs: Increased seizure risk
Complete interaction check required before prescribing - consult our doctors.
Mysimba Side Effects Profile
Common adverse reactions (≥1/10 users):
- Gastrointestinal: Nausea (32%), constipation (19%), vomiting (11%)
- Neurological: Headache (26%), dizziness (9%)
- Psychiatric: Anxiety (14%), insomnia (12%)
Serious risks requiring immediate medical attention:
- Seizures (0.1% incidence)
- Increased blood pressure (2-3 mmHg average)
- Suicidal ideation (monitor mood changes)
Mysimba Allergy Information
Contraindicated in patients with:
- Known hypersensitivity to naltrexone/bupropion
- Lactose intolerance (contains lactose monohydrate)
- Phenylketonuria (contains aspartame)
Anaphylaxis signs requiring emergency care:
- Angioedema (facial swelling)
- Respiratory distress (wheezing)
- Urticaria (hives)
Mysimba in Pregnancy & Breastfeeding
Pregnancy Category: Avoid - potential fetal risks
Lactation: Contraindicated - excreted in breast milk
Required precautions:
- Negative pregnancy test before treatment
- Effective contraception during therapy
- Immediate discontinuation if pregnancy occurs
Essential Safety Information
- Storage: Below 25°C in original packaging
- Disposal: Return unused tablets to pharmacy
- Expiry: Do not use past printed date
- Monitoring: BP checks every 3 months
Where to Buy Mysimba Safely Online in the UK
When purchasing prescription weight loss medication like Mysimba (naltrexone/bupropion), it's essential to use GPhC-registered online pharmacies. Chemist Doctor provides:
- MHRA-approved medications
- GMC-registered doctor consultations
- GDPR-compliant secure platform
Why Choose Chemist Doctor for Mysimba Treatment?
Our complete weight management service includes:
- Secure online consultation with UK doctors
- Discreet next-day delivery service
- Ongoing progress monitoring
Mysimba Treatment Journey with Chemist Doctor
Step 1: Medical Assessment
Our prescribers verify:
- Current BMI (via photo evidence)
- Medical history review
- Contraindication screening
Step 2: Ongoing Support
- Dose adjustment consultations
- Side effect management
- Diet/exercise planning
Start Your Safe Weight Loss Journey
Begin your online consultation and receive genuine Mysimba tablets with next-day delivery if approved by our doctors.
Getting your medication is quick and easy with our simple 4-step process:
Start Consultation
Complete our brief health questionnaire about your medical history and current health.
Medical Review
UK-registered clinicians review your consultation for safe prescribing.
Pharmacy Processing
If approved, our partner pharmacy prepares your medication.
Fast Dispatch
Your order is dispatched via your chosen delivery method.
What does the online consultation involve?
You'll answer questions about your medical history and current health to ensure safe prescribing. Honest responses are vital for your safety.
How do I reorder medication?
Use the login details emailed after your first order to access your account and reorder.
How does the secure chat portal work?
Clinicians may contact you via your account's chat portal to discuss your treatment. Respond securely within your account.
At Chemist Doctor, we respect your privacy and ensure complete discretion at every step.
Discreet Packaging
All orders are shipped in discreet, tamper-evident packaging sealed inside anonymous mailing bags.
Secure Data
Your personal and medical information is kept strictly confidential with SSL encryption.
Private Consultations
All consultations are conducted privately by UK-registered clinicians.
Anonymous Billing
Credit card statements show a neutral descriptor with no reference to medications.
Will my GP be informed about my order?
Only with your consent. We recommend updating your GP directly for seamless care.
We offer two reliable delivery options to suit your needs:
| Service Type | Delivery Speed | Order Cut-off | Carrier |
|---|---|---|---|
| Standard Delivery | 2-3 business days | No cut-off | Royal Mail |
| Premium Next-Day Delivery | Next business day | 3 PM weekdays | Royal Mail 24 |
Next-day delivery guarantee applies to orders approved before 3 PM to these regions:
- England
- Scotland
- Wales
- Northern Ireland
Service Restrictions: We currently cannot deliver to: Republic of Ireland, Continental Europe, USA, or Canada
Is packaging discreet?
Yes. All orders are shipped in plain, unmarked packaging via tracked courier services.
Do I need to stay home for delivery?
No. You'll receive a tracking number to monitor your parcel's progress.
Do you deliver on weekends or bank holidays?
Deliveries occur Monday–Friday only. We do not ship on weekends or UK bank holidays.
What should I do if my order hasn't arrived?
Use your tracking number to locate the parcel or contact our support team for assistance.
Can I receive delivery updates via SMS?
Yes. Provide your mobile number at checkout for courier updates. We will not use it for marketing purposes.
Credit/Debit Cards
Visa, Mastercard, Maestro, American Express
Secure 3D authentication
Bank Transfer
Select at checkout for unique reference details
Order processes once payment clears
We use SSL encryption and PCI DSS compliance to secure transactions. Learn more in our Privacy Policy.
How long do refunds take to process?
Card payments: Refunds appear in 3–5 days.
Bank transfers: We'll contact you for account details to return funds.
Why was my order declined?
Declined orders are not charged. Card authorisations release funds within 3–5 days (contact your bank for details).
Can I return prescription medication?
No. UK law prohibits returns of dispensed prescription treatments for safety reasons.
Reviews being updated...
Have you used our services? Share your experience
Mysimba FAQs
How Effective Is Mysimba?
In studies, more than 40% of people taking Mysimba lost 5% of their body weight over the course of 28 or 56 weeks.
Can I Drink Alcohol While Taking Mysimba?
You should avoid or limit alcohol consumption while taking Mysimba for weight loss. Alcoholic drinks are generally high in calories and can put you at an increased risk of complications from obesity.
Will Mysimba Affect My Ability to Drive or Operate Machinery?
Mysimba may cause you to feel drowsy or dizzy. If you notice that this medicine has this effect on you, you should avoid driving or operating any machinery until you are well enough to do so.
Is Mysimba Available on the NHS?
No, Mysimba is not typically available on the NHS. However, it is available from Prescription Doctor's online private prescription service.
Simply fill out our short medical questionnaire, and our online prescriber will determine whether Mysimba is suitable for you.
How Long Can I Take Mysimba?
You should take Mysimba for at least 16 weeks in order for it to reach its maximum effect.
Mysimba can be taken for as long as required to achieve your weight loss goal. You should not stop taking Mysimba without first speaking to your doctor.
Can I Use Mysimba Alongside Other Weight Loss Treatments, Like Orlistat or Saxenda?
Do not use Mysimba together with Orlistat or Saxenda. If you wish to change the weight loss medication you are taking, speak to your doctor.
Can I take Mysimba without dieting?
No - Mysimba must be combined with calorie restriction and exercise for effectiveness.
How long until I see results?
Assess progress at 16 weeks - discontinue if <5% weight loss (per NICE TA539).
 | Authored by Nabeel M |
Medical Content Manager & Pharmacy Associate
Nabeel is a co-founder of Chemist Doctor. He works closely with our medical team to ensure the information is accurate and up-to-date.
 | Reviewed by Usman M (2073618) |
Director & Superintendent Pharmacist
Usman is a co-founder, and superintendent pharmacist of Chemist Doctor. He leads the clinical team and online prescribing services, utilising his expertise.
Review Date: 01 May 2025
Next Review: 04 December 2025
Published on: 01 May 2025
Last Updated: 02 May 2025
Responsible Pharmacist
 | Usman Mir Superintendent GPhc: 2073618 |
We Are Regulated
 |  |  |
 |  |  |
 |  |
Chemist Doctor is an online pharmacy and online doctor service, owned and operated by Chem Doc Ltd (Company Reg. 16478812). Prescriptions are managed by our sister company, Inspire Pharmacy (GPhC No. 9011381), a registered pharmacy located at Unit 18, Croft Road Industrial Estate, Newcastle-under-Lyme, Staffordshire, ST5 0TW. The content on this website is for informational purposes only. It should support, not replace, advice from your healthcare provider. Always consult your doctor if you suspect a health issue or before beginning new medication. Ensure you read the leaflets provided with any medicines. For further details, visit our policies and terms & conditions at the bottom of each page.
 |  |  |  |
Copyright 2025 Chemist Doctor. All Rights Reserved