Tirzepatide (Mounjaro/Zepbound) is the newest and most effective GLP-1 medication available. Like semaglutide, it requires careful dose titration. Here's everything you need to know about tirzepatide dosing.
Tirzepatide Overview
Tirzepatide is unique because it's a dual GIP/GLP-1 receptor agonist:
- Activates both GLP-1 and GIP receptors
- Shows greater weight loss than semaglutide in studies
- Available as Mounjaro (diabetes) and Zepbound (weight loss)
- Weekly injection like Ozempic/Wegovy
Why Titration Is Critical
Tirzepatide is highly potent. Starting at the full dose would cause severe GI side effects in most people. The 4-week intervals at each dose allow your body to adapt gradually.
Mounjaro/Zepbound Dosage Schedule
Both Mounjaro and Zepbound use the same tirzepatide doses and titration schedule:
| Period | Dose | Duration | Notes |
|---|---|---|---|
| Weeks 1-4 | 2.5 mg | 4 weeks | Starting dose (not therapeutic) |
| Weeks 5-8 | 5 mg | 4 weeks | First therapeutic dose |
| Weeks 9-12 | 7.5 mg | 4 weeks | Increased effect |
| Weeks 13-16 | 10 mg | 4 weeks | Strong therapeutic effect |
| Weeks 17-20 | 12.5 mg | 4 weeks | Near maximum effect |
| Week 21+ | 15 mg | Ongoing | Maximum dose |
Time to maximum dose: 20 weeks (approximately 5 months)
Available Pen Strengths
Tirzepatide comes in single-dose pens at specific strengths:
| Pen Strength | Color | Doses per Box |
|---|---|---|
| 2.5 mg | Yellow/beige | 4 pens (1 month) |
| 5 mg | Maroon/red | 4 pens (1 month) |
| 7.5 mg | Green | 4 pens (1 month) |
| 10 mg | Teal/turquoise | 4 pens (1 month) |
| 12.5 mg | Blue | 4 pens (1 month) |
| 15 mg | Purple | 4 pens (1 month) |
What to Expect at Each Dose Level
2.5 mg (Starting Dose)
- Appetite: Minimal change expected
- Weight loss: Little to none
- Side effects: Mild or none
- Purpose: Allow body to adjust
5 mg (First Therapeutic Dose)
- Appetite: Noticeable reduction for most
- Weight loss: Typically begins
- Side effects: Nausea possible
- Purpose: First effective dose
7.5 mg
- Appetite: Strong suppression
- Weight loss: Significant progress
- Side effects: May temporarily increase
- Purpose: Many stabilize here
10 mg
- Appetite: Very strong suppression
- Weight loss: Continuing acceleration
- Side effects: Usually adapted
- Purpose: Common maintenance dose
12.5 mg
- Appetite: Near maximum effect
- Weight loss: Approaching full potential
- Side effects: Stable for most
- Purpose: Higher maintenance option
15 mg (Maximum)
- Appetite: Maximum suppression
- Weight loss: Full potential (20-25%+ body weight)
- Side effects: Variable
- Purpose: Maximum dose for those who need it
Not Everyone Needs Maximum Dose
Clinical trials show excellent results at 5-10 mg for many people. If you're losing weight steadily and tolerating your current dose, you may not need to increase further. The maximum dose isn't the goal—effective weight loss with manageable side effects is.
Tirzepatide vs Semaglutide Dosing Comparison
| Aspect | Tirzepatide | Semaglutide |
|---|---|---|
| Starting dose | 2.5 mg | 0.25 mg |
| Maximum dose | 15 mg | 2.4 mg (Wegovy) |
| Time to max | ~20 weeks | ~17 weeks |
| Dose levels | 6 levels | 5 levels |
| Injection frequency | Weekly | Weekly |
| Average weight loss | ~21% (15 mg) | ~15% (2.4 mg) |
Compounded Tirzepatide Dosing
Compounded tirzepatide typically follows similar titration:
- Usually starts at 2.5 mg weekly
- Titrates every 4 weeks
- Maximum doses vary by provider (typically up to 15 mg)
- Some providers use slightly different schedules
Compounding Availability
Compounded tirzepatide is available because brand-name is on the FDA shortage list. This allows compounding pharmacies to legally produce it at lower cost. However, if the shortage ends, compounding may no longer be available.
Managing Side Effects During Titration
Common Side Effects
- Nausea: Most common, peaks after dose increases
- Diarrhea: Common, especially early on
- Constipation: Some experience this instead
- Decreased appetite: Expected (it's the point!)
- Injection site reactions: Usually mild
Tips for Each Dose Increase
- Eat smaller, more frequent meals
- Avoid greasy, fatty, and fried foods
- Stop eating before you feel full
- Stay well hydrated
- Take dose at same time each week
- Give yourself 2-4 weeks to adjust
When to Increase vs. Stay at Current Dose
Consider Staying If:
- Still having significant side effects
- Weight loss is progressing well
- Appetite is well controlled
- Comfortable at current dose
Consider Increasing If:
- Side effects have resolved
- Weight loss has slowed/plateaued
- Appetite suppression has weakened
- Not yet at goal weight
Don't Skip Doses
Never skip dose levels to reach maximum faster. This dramatically increases GI side effects and doesn't improve long-term results. The 4-week intervals are essential for tolerability.
Frequently Asked Questions
Can I stay at a lower dose permanently?
Yes. Many people achieve excellent results at 5-10 mg and stay there long-term. The maximum dose is available for those who need it, but it's not required for everyone.
What if I can't tolerate a dose increase?
Stay at your current tolerated dose for additional weeks before trying again. Some people benefit from 6-8 weeks at a dose before increasing. You can also work with your provider to try a slower titration.
Is tirzepatide stronger than semaglutide?
Clinical trials show tirzepatide produces more weight loss on average (~21% vs ~15%). However, individual responses vary. Some people respond better to one medication than the other.
How long until I see weight loss?
Most people start seeing weight loss by weeks 4-8 (at the 5 mg dose). Significant weight loss typically occurs over 6-12 months as you reach and maintain therapeutic doses.
Can I switch from semaglutide to tirzepatide?
Yes, but dosing doesn't directly convert. Most providers start tirzepatide at 2.5 mg regardless of previous semaglutide dose, though some may start at 5 mg for those already on higher semaglutide doses.
Conclusion
Tirzepatide offers the most effective weight loss results currently available, but requires patient titration over 5+ months. The key is following the schedule, managing side effects, and finding the dose that works best for you—which may or may not be the maximum.
Work with your healthcare provider to optimize your dosing. Remember that the goal is effective, sustainable weight loss with tolerable side effects, not reaching the maximum dose as quickly as possible.
Key Takeaway
Tirzepatide titrates from 2.5 mg to 15 mg over ~20 weeks. Many people achieve excellent results at 5-10 mg. Patience with the titration schedule dramatically reduces side effects and improves tolerability.
Related Reading
Compare with semaglutide dosing: Semaglutide Dosage Chart.