Last updated: 2 December 2024 | Medically reviewed by Dr M. Gough

Key Facts at a Glance

Active Ingredient: Tirzepatide
Administration: Weekly subcutaneous injection
UK Approval: Type 2 diabetes (NHS), Weight management (Private)
Average Weight Loss: 15-22.5% body weight over 72 weeks
UK Cost: £174-289 per month (private prescription)
Starting Dose: 2.5mg weekly for 4 weeks

What is Mounjaro?

Mounjaro (tirzepatide) is a once-weekly injectable medication approved in the UK for treating type 2 diabetes and, through private prescription, for weight management in adults with obesity or overweight with weight-related health conditions.

Table of Contents

Manufactured by Eli Lilly, Mounjaro was approved by the UK Medicines and Healthcare products Regulatory Agency (MHRA) in September 2022 for type 2 diabetes and is available for weight management through private healthcare providers.

Quick Overview

Generic Name	Tirzepatide
Brand Name	Mounjaro
Drug Class	Dual GIP/GLP-1 receptor agonist
Manufacturer	Eli Lilly and Company
UK Approval Date	September 2022 (diabetes), 2023 (weight management – private)
Available Doses	2.5mg, 5mg, 7.5mg, 10mg, 12.5mg, 15mg

What Makes Mounjaro Different?

Unlike other weight loss medications such as Wegovy (semaglutide), which target only GLP-1 receptors, Mounjaro is a dual-action medication that targets both GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like peptide-1) receptors.

This dual mechanism has demonstrated superior weight loss outcomes compared to single-action GLP-1 medications in clinical trials, with patients losing an average of 15-22.5% of their body weight over 72 weeks.

How Mounjaro Works: Mechanism of Action

Mounjaro works by mimicking two naturally occurring hormones in your body: GIP and GLP-1. These hormones play crucial roles in regulating blood sugar levels and appetite control.

The Dual-Action Mechanism

GLP-1 (Glucagon-Like Peptide-1) Action:

Appetite Suppression: Signals to your brain that you’re full, reducing overall food intake
Delayed Gastric Emptying: Slows down how quickly food leaves your stomach, keeping you fuller for longer
Blood Sugar Control: Stimulates insulin release when blood sugar is elevated
Glucagon Reduction: Reduces glucagon secretion, preventing excess glucose production

GIP (Glucose-Dependent Insulinotropic Polypeptide) Action:

Enhanced Insulin Response: Works synergistically with GLP-1 to improve insulin secretion
Fat Metabolism: May influence how your body stores and uses fat
Energy Expenditure: Potentially increases the calories your body burns at rest

Why Dual Action Matters

The combination of GIP and GLP-1 receptor activation appears to produce greater weight loss than GLP-1 alone. In head-to-head trials comparing Mounjaro to Ozempic (semaglutide, a GLP-1-only medication), Mounjaro demonstrated superior weight loss outcomes:

Medication	Mechanism	Average Weight Loss (72 weeks)
Mounjaro 15mg	Dual GIP/GLP-1	22.5%
Wegovy 2.4mg	GLP-1 only	15-16%
Ozempic 2mg	GLP-1 only	12-14%
Saxenda 3mg	GLP-1 only	7-9%

Source: SURMOUNT-1 trial data (NEJM, 2022); STEP trials; Saxenda prescribing information

Clinical Evidence: What the Research Shows

Mounjaro’s effectiveness has been demonstrated in multiple large-scale clinical trials, most notably the SURMOUNT trial series for weight management and SURPASS trials for diabetes management.

SURMOUNT-1 Trial: Weight Loss Results

The SURMOUNT-1 trial, published in the New England Journal of Medicine in 2022, enrolled 2,539 adults with obesity or overweight (without diabetes) and tracked their progress over 72 weeks.

Average Weight Loss by Dose (72 weeks):

Treatment Group	Average Weight Loss (%)	Average Weight Loss (kg)	Patients Losing >20% Body Weight
Placebo	3.1%	3.5kg	3%
Mounjaro 5mg	15.0%	15.9kg	30%
Mounjaro 10mg	19.5%	21.1kg	50%
Mounjaro 15mg	22.5%	24.7kg	63%

Real-World Weight Loss Timeline

Based on clinical trial data, here’s what patients typically experience:

Time Period	Expected Weight Loss	What to Expect
Weeks 1-4	1-3% body weight	Initial dose (2.5mg), reduced appetite, possible mild nausea
Weeks 5-8	3-5% body weight	Dose increase to 5mg, continued appetite suppression
Weeks 9-16	6-10% body weight	Further dose increases, weight loss accelerates
Weeks 17-36	10-15% body weight	Peak dose achieved, steady weight loss continues
Weeks 37-72	15-22.5% body weight	Maintenance phase, weight stabilizes at lower level

⚠️ Important Considerations:

Individual results vary based on starting weight, adherence, lifestyle factors, and dose
Maximum weight loss typically occurs between 60-72 weeks
Behavioral changes (diet, exercise) significantly improve outcomes
Weight regain can occur if medication is discontinued without lifestyle maintenance

Additional Health Benefits

Beyond weight loss, Mounjaro has demonstrated improvements in:

Blood Pressure: Average reduction of 7-10 mmHg systolic
Cholesterol: Improvements in HDL and triglycerides
HbA1c: Significant reductions in patients with prediabetes or diabetes
Liver Function: Improvements in non-alcoholic fatty liver disease markers
Inflammation: Reduced C-reactive protein levels

Mounjaro Dosing Schedule: How to Use It

Mounjaro follows a gradual dose escalation protocol to minimize side effects while maximizing effectiveness. The medication is self-administered once weekly via a pre-filled injection pen.

Standard Dose Escalation Schedule

Weeks	Dose	Purpose	What to Expect
1-4	2.5mg	Initiation dose – allow body to adjust	Mild appetite reduction, possible minor nausea
5-8	5mg	First increase – therapeutic effect begins	Noticeable appetite suppression, steady weight loss
9-12	7.5mg	Continued escalation	Increased weight loss rate
13-16	10mg	Therapeutic dose for many patients	Strong appetite control, consistent weight loss
17-20	12.5mg	Optional higher dose	Enhanced effects for some patients
21+	15mg	Maximum dose (if tolerated and needed)	Maximum therapeutic benefit

Important Dosing Notes:

Doses must be increased gradually – never skip steps
Not everyone needs to reach 15mg – many patients achieve goals at 10mg
Your prescriber will determine the right dose based on your response and tolerability
If you experience significant side effects, your dose increase may be delayed

How to Inject Mounjaro

Choose injection site: Abdomen (5cm away from belly button), thigh, or upper arm
Rotate sites: Use different areas each week to prevent irritation
Prepare pen: Check expiry date, allow to reach room temperature (15-30 min)
Clean site: Use alcohol wipe and let dry completely
Inject: Press pen firmly against skin, press button, hold for 10 seconds
Dispose safely: Place used pen in sharps container

Best Time to Inject

Mounjaro can be taken at any time of day, with or without food. Most patients prefer:

Evening: Sleep through any initial nausea
Same day each week: Consistency improves adherence (e.g., every Sunday evening)
Before a lighter eating day: Some patients prefer weekends when appetite reduction is easier to manage

What If You Miss a Dose?

Within 4 days: Take it as soon as you remember, then resume normal schedule
More than 4 days: Skip the missed dose and take next dose on regular day
Never double dose to make up for a missed injection

Storage Requirements

Unopened pens: Store in refrigerator (2-8°C)
In-use pens: Can be kept at room temperature (up to 30°C) for up to 21 days
Do not freeze – if frozen, discard the pen
Protect from light: Keep in original carton until use
Travel: Use insulated bag with ice pack for journeys over 30 minutes

For more detailed information about Mounjaro’s approval and safety profile, refer to the NICE guidance on tirzepatide for treating type 2 diabetes, which provides comprehensive clinical recommendations for UK healthcare providers.

The clinical evidence for Mounjaro’s effectiveness comes from the landmark SURMOUNT-1 trial, published in the New England Journal of Medicine, which demonstrated significant weight loss outcomes across different dosage levels.

Patients should always consult with healthcare professionals before starting any weight loss medication. For additional support and information about obesity management, visit the NHS obesity treatment guidelines, which outline comprehensive approaches to weight management in the UK.

Mounjaro Side Effects: What to Expect

Like all medications, Mounjaro can cause side effects. Most are mild to moderate and typically improve as your body adjusts to the medication, particularly after dose increases.

Common Side Effects (Affecting 10%+ of Patients)

Side Effect	Frequency	Severity	Management Strategies
Nausea	25-35%	Mild-Moderate	Eat smaller meals, avoid fatty/spicy foods, ginger tea, usually resolves after 1-2 weeks
Diarrhea	18-25%	Mild-Moderate	Stay hydrated, avoid trigger foods, probiotics may help
Decreased appetite	20-30%	Mild (intended effect)	Focus on nutrient-dense foods, protein-rich small meals
Constipation	15-20%	Mild-Moderate	Increase fiber, hydration, gentle exercise, consider stool softener
Vomiting	8-12%	Moderate	Eat slowly, smaller portions, avoid lying down after eating
Fatigue	10-15%	Mild	Ensure adequate calorie/protein intake, improve sleep hygiene
Injection site reactions	5-10%	Mild	Rotate injection sites, cold compress, usually resolves quickly

Side Effect Timeline

Understanding when side effects occur helps manage expectations:

Days 1-3 after first injection: Most common time for initial nausea/GI symptoms
Week 2-4: Symptoms typically improve significantly
After dose increases: Mild return of symptoms for 3-7 days, then improvement
Weeks 12+: Most patients report minimal ongoing side effects

Rare but Serious Side Effects (Seek Medical Attention)

⚠️ Contact your doctor immediately if you experience:

Severe abdominal pain: Especially if persistent and radiating to back (possible pancreatitis)
Vision changes: Sudden blurriness or vision loss (diabetic retinopathy concerns)
Rapid heartbeat or palpitations: Unusual heart rhythm
Severe allergic reaction: Difficulty breathing, swelling of face/throat, severe rash
Signs of thyroid tumor: Lump in neck, hoarseness, trouble swallowing (extremely rare)
Severe hypoglycemia: Confusion, sweating, shakiness (mainly if combined with insulin/sulfonylureas)
Kidney problems: Reduced urination, swelling in legs, severe dehydration
Gallbladder issues: Sudden upper right abdominal pain, fever, yellowing of skin

Who Experiences More Side Effects?

Side effects tend to be more common in:

Patients with pre-existing gastrointestinal conditions
Those who increase doses too quickly
Individuals with a history of pancreatitis
Patients taking other medications affecting GI function

Minimizing Side Effects: Best Practices

Slow dose escalation: Follow the prescribed schedule exactly
Dietary adjustments: Smaller, more frequent meals; avoid fatty, spicy, or heavy foods
Stay hydrated: At least 2 liters of water daily
Protein first: Prioritize protein to maintain muscle mass and reduce nausea
Timing of meals: Eat 1-2 hours before or after injection if nausea is problematic
Anti-nausea aids: Ginger, peppermint, small sips of clear fluids
Physical activity: Gentle exercise can help with constipation and energy levels

💡 Why Behavioral Support Matters

At Evernu, we provide behavioral health support alongside Mounjaro prescriptions specifically to help you manage side effects and optimize your treatment. Our approach includes:

Personalized meal planning to minimize GI symptoms
Strategies for maintaining protein intake despite reduced appetite
Mental health support for the psychological aspects of rapid weight loss
Regular check-ins to adjust treatment as needed

Learn more about our behavioral health program →

Who Can Take Mounjaro? Eligibility Criteria

Mounjaro is not suitable for everyone. UK prescribers follow specific clinical guidelines to determine eligibility for treatment.

Standard Eligibility Criteria (Private Prescription)

Requirement	Details
Age	18 years or older (not approved for children/adolescents in UK)
BMI	BMI ≥30 (obese), OR BMI ≥27 with weight-related health condition (type 2 diabetes, high blood pressure, sleep apnea, etc.)
Weight Loss History	Previous unsuccessful attempts at diet and exercise (typically 6+ months)
Commitment	Willingness to make lifestyle changes (diet, exercise) alongside medication

NHS Eligibility (Type 2 Diabetes Only)

As of December 2024, NHS prescriptions for Mounjaro are limited to patients with type 2 diabetes who meet specific NICE criteria:

Diagnosed type 2 diabetes
BMI ≥35 (or ≥32.5 for people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean descent)
HbA1c above target despite other treatments
Already tried metformin and at least one other diabetes medication

Note: NHS weight management use of Mounjaro is not yet routinely available. Most patients seeking Mounjaro for weight loss require private prescription.

Medical Conditions That May Affect Eligibility

⚠️ Absolute Contraindications (Cannot Use):

History of medullary thyroid carcinoma (MTC)
Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)
Personal or family history of MTC
Severe allergic reaction to tirzepatide or ingredients
Pregnancy or breastfeeding
Type 1 diabetes (not indicated)

⚠️ Requires Caution (Discuss with Prescriber):

History of pancreatitis
Severe gastrointestinal disease (gastroparesis, inflammatory bowel disease)
Diabetic retinopathy (requires monitoring)
Kidney disease (dose adjustments may be needed)
Gallbladder disease or gallstones
History of depression or suicidal thoughts
Taking other weight loss medications
Planning pregnancy within next 6-12 months

Medication Interactions

Inform your prescriber if you’re taking:

Medication Type	Potential Interaction	Action Needed
Insulin or sulfonylureas	Increased risk of hypoglycemia	Dose reduction of insulin/sulfonylurea may be required
Oral contraceptives	May reduce absorption in first 4 weeks	Use backup contraception for 4 weeks after starting
Warfarin	May affect INR	More frequent INR monitoring initially
Other GLP-1 agonists	Should not be combined	Choose one medication only

Pregnancy and Breastfeeding

⚠️ Important: Mounjaro is not recommended during pregnancy or breastfeeding.

If planning pregnancy: Stop Mounjaro at least 2 months before trying to conceive
If you become pregnant: Stop taking Mounjaro immediately and contact your healthcare provider
Breastfeeding: Unknown if Mounjaro passes into breast milk – discuss alternatives with your doctor
Contraception: Use reliable contraception while taking Mounjaro

Check Your Eligibility

Not sure if you’re eligible for Mounjaro? At Evernu, our clinical team can assess your suitability during a free 15-minute consultation.

Book Free Eligibility Assessment →

How Much Does Mounjaro Cost in the UK?

Mounjaro pricing in the UK varies significantly depending on whether you’re accessing it through the NHS (limited availability) or private prescription services. As of December 2025, private costs have increased following Eli Lilly’s September 2025 price rises.

Private Prescription Costs (December 2025)

Provider	Monthly Cost	What’s Included	Additional Notes
Evernu	£174.25/month	Medication (all doses) Clinical consultation Behavioral health support Ongoing monitoring UK delivery included	No hidden fees, cancel anytime
Medicspot	£149-329/month	Medication Online consultation Delivery	Cheapest option, basic service
Boots Online Doctor	£179-299/month	Medication Consultation Delivery	Higher doses cost more
Superdrug Online Doctor	£215-245/month	Medication Consultation Delivery	Mid-range pricing
Second Nature	£229-349/month	Medication Consultation App & coaching support	Premium service with coaching

Cost Breakdown: What You’re Really Paying For

Understanding the components of Mounjaro costs:

Medication itself: ~£120-180 wholesale cost per month (varies by dose)
Clinical assessment: £30-60 (consultation, eligibility review, prescription)
Ongoing monitoring: £20-40 (monthly check-ins, dose adjustments)
Dispensing & delivery: £10-20
Behavioral support: £30-50 (when included – Evernu only)

Annual Cost Comparison

Weight loss treatment is typically a 12-18 month commitment. Here’s what to budget:

Provider	12-Month Total	18-Month Total	Cost Per % Body Weight Lost*
Evernu	£2,091	£3,137	£93-139/% lost
Medicspot (avg)	£2,748	£4,122	£122-183/% lost
Boots (avg)	£2,868	£4,302	£127-191/% lost
Second Nature (avg)	£3,468	£5,202	£154-231/% lost

*Based on average 15-22.5% body weight loss in clinical trials

NHS Availability & Costs

NHS prescription charges for Mounjaro (diabetes patients only):

England: £9.90 per prescription (covers 4 weekly doses = ~£2.50/week)
Scotland: Free prescriptions
Wales: Free prescriptions
Northern Ireland: Free prescriptions

Important: NHS coverage for weight loss is extremely limited and currently restricted to patients with BMI over 40 (or 37.5 for ethnic minorities) plus multiple weight-related conditions. Most patients seeking weight loss treatment require private prescription.

Why Evernu Offers Exceptional Value

At £174.25/month, Evernu provides comprehensive care while remaining cost-competitive:

Feature	Evernu	Basic Competitors	Premium Competitors
Monthly cost	£174.25	£149-245	£229-349
Behavioral support	✅ Included	❌ Not included	✅ App-based only
Dedicated clinical team	✅ Personal support	❌ Generic service	⚠️ App-based
Flexible cancellation	✅ Anytime	⚠️ Varies	⚠️ Varies
Clinical monitoring	✅ Ongoing	❌ Basic	✅ Yes

12-month savings vs premium competitors: £900-1,380
Added value vs basic competitors: Behavioral support + dedicated clinical care

View Full Pricing Details →

Payment Options

Monthly subscription: £174.25/month, cancel anytime (most popular)
3-month prepay: Save 5% (£165.54/month = £496.61 upfront)
6-month prepay: Save 10% (£156.83/month = £941.00 upfront)

All major credit/debit cards accepted. Delivery included across the UK.

Ready to Start Your Weight Loss Journey?

Get Mounjaro for £174.25/month – including clinical support, behavioral coaching, and ongoing monitoring.

✅ No hidden fees ✅ Cancel anytime ✅ UK-qualified doctors ✅ Comprehensive support

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