Weight Loss Medications Comparison 2025
Mounjaro vs Wegovy vs Ozempic vs Saxenda - Which is Right for You?
Updated: 31 July 2025 | 12 min read
Quick Comparison Table
| Medication | Active Ingredient | Average Weight Loss | Injection Frequency | Monthly Cost (UK) |
|---|---|---|---|---|
| Mounjaro | Tirzepatide | 15-22% | Weekly | £120-350 |
| Wegovy | Semaglutide 2.4mg | 12-15% | Weekly | £200-300 |
| Ozempic | Semaglutide 1mg | 8-12% | Weekly | £130-250 |
| Saxenda | Liraglutide | 5-10% | Daily | £150-250 |
Detailed Medication Profiles
Mounjaro (Tirzepatide)
Pros:
- Highest average weight-loss
- Dual hormone action (GIP/GLP-1)
- Once weekly injection
- Good availability in UK
Cons:
- Can be expensive at higher doses
- Newer medication (less long-term data)
- Common GI side effects initially
Best for: Those seeking maximum weight-loss who can tolerate gradual dose escalation.
Wegovy (Semaglutide 2.4mg)
Pros:
- Specifically approved for weight-loss
- Extensive clinical trial data
- Once weekly injection
- Proven cardiovascular benefits
Cons:
- Supply shortages in UK
- Expensive when available
- May cause nausea
Best for: Those who want a well-established weight-loss medication with strong clinical evidence.
Ozempic (Semaglutide 1mg)
Pros:
- More affordable than Wegovy
- Better availability
- Once weekly injection
- Diabetes benefits
Cons:
- Lower dose than Wegovy
- Off-label for weight-loss
- Less weight-loss than Wegovy/Mounjaro
Best for: Those with type 2 diabetes or seeking a more affordable semaglutide option.
Saxenda (Liraglutide)
Pros:
- Established safety profile
- Approved for weight-loss
- Can work when others fail
Cons:
- Daily injections required
- Less effective than newer options
- More injection site reactions
Best for: Those who haven't responded to weekly medications or prefer daily dosing.
Side Effects Comparison
All GLP-1 medications share similar side effects, typically most pronounced when starting or increasing doses:
Most Common
- ✓ Nausea
- ✓ Diarrhea
- ✓ Constipation
- ✓ Vomiting
- ✓ Decreased appetite
Less Common
- ✓ Headache
- ✓ Fatigue
- ✓ Dizziness
- ✓ Heartburn
- ✓ Hair loss (rare)
Serious (Rare)
- ⚠️ Pancreatitis
- ⚠️ Gallbladder problems
- ⚠️ Kidney problems
- ⚠️ Allergic reactions
- ⚠️ Thyroid tumors
How to Choose
- Maximum weight-loss: Mounjaro or Wegovy
- Moderate weight-loss: Ozempic
- Modest weight-loss: Saxenda
Use our price comparison tool to find current best prices. Generally:
- Most affordable: Starting doses of any medication
- Best value: Mounjaro (considering effectiveness)
- Budget option: Ozempic (if weight-loss goals are moderate)
As of 2025 in the UK:
- Best availability: Mounjaro, Ozempic
- Limited availability: Wegovy (frequent shortages)
- Good availability: Saxenda
Starting Your Weight Loss Journey
- Consult a healthcare provider - Discuss your medical history and goals
- Get baseline measurements - Weight, BMI, blood tests
- Choose your medication - Based on effectiveness, cost, and availability
- Find the best price - Use our comparison tool
- Start slowly - Follow the dosing schedule
- Track progress - Weight, measurements, how you feel
- Adjust as needed - Work with your provider
Remember
All weight-loss medications work best when combined with:
- Reduced calorie diet
- Regular physical activity
- Behavioral changes
- Adequate sleep
- Stress management
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