The head-to-head comparison
| Attribute | Ozempic | Mounjaro |
|---|---|---|
| Active molecule | Semaglutide | Tirzepatide |
| Mechanism | GLP-1 agonist (single) | GIP/GLP-1 dual agonist |
| Manufacturer | Novo Nordisk | Eli Lilly |
| Dose range | 0.25-1.0mg weekly | 2.5-15mg weekly |
| TGA indication | Type 2 diabetes | Type 2 diabetes |
| PBS subsidised? | Yes (T2D only) | No |
| PBS price | $31.60 general / $7.70 concession | N/A |
| Private cost/month | $380-$450 | $450-$580 |
| Telehealth bundle | $290-$420/month | $400-$550/month |
| Trial weight loss | ~15% (Wegovy 2.4mg, STEP) | ~20% (15mg, SURMOUNT-1) |
| Injection frequency | Weekly | Weekly |
| Titration phase | ~16 weeks (4 doses) | ~20-24 weeks (6 doses) |
How the medicines differ
Tirzepatide (Mounjaro) acts on two distinct receptor families, GIP (glucose-dependent insulinotropic polypeptide) and GLP-1. Semaglutide (Ozempic) acts on GLP-1 only. The clinical-trial programmes for the two medicines (SURMOUNT for tirzepatide, STEP for semaglutide) are not strictly head-to-head; do not read a direct ranking into the published numbers without your prescriber's interpretation. The TGA Product Information for each medicine is the authoritative source for indications, dosing and safety information.
Questions to discuss with your prescriber
Decisions between TGA-approved options are clinical, not consumer choices. Discuss the following with an AHPRA-registered prescriber:
- Which (if any) GLP-1 medicine is appropriate for your clinical picture and on-label use
- What baseline assessment and monitoring is required
- How PBS eligibility applies in your circumstances
- What side-effect profile you should expect and how to manage early titration
- If you are on one medicine and considering switching, the safe washout and titration approach
See also our general information pages on Wegovy and Ozempic.
How to switch between Ozempic and Mounjaro
Switching requires prescriber guidance because the molecules are different (unlike Ozempic↔Wegovy which share the same molecule):
- Discuss with your prescriber. Confirm clinical appropriateness and cost/benefit. Document the reason (insufficient weight loss, side effect intolerance, supply issue).
- Use up current supply. Take your final Ozempic dose at the scheduled time.
- Wait 7 days washout. Allows semaglutide to clear; reduces overlap of pharmacologic effects.
- Start Mounjaro at lowest dose. 2.5mg weekly for 4 weeks regardless of previous Ozempic dose. Don’t jump to your previous "equivalent" dose.
- Titrate up gradually. 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg over 5-6 months.
- Monitor weight, side effects, HbA1c. Expect a brief "honeymoon" of better weight loss in months 1-3 as the new mechanism takes effect.
Switching in the reverse direction (Mounjaro → Ozempic) follows the same pattern with a washout and dose restart.
12-month cost comparison
For an Australian patient without T2D paying privately:
| Pathway | 12-month total (AUD) |
|---|---|
| Off-label Ozempic (retail pharmacy + GP) | $5,000-$6,500 |
| Off-label Ozempic (telehealth) | $3,500-$5,000 |
| Wegovy (retail pharmacy + GP) | $5,400-$7,000 |
| Wegovy (telehealth) | $3,500-$5,400 |
| Mounjaro (retail pharmacy + GP) | $5,800-$7,800 |
| Mounjaro (telehealth) | $4,800-$6,600 |
| PBS Ozempic (T2D, general) | $379 |
| PBS Ozempic (T2D, concession) | $92 |
The PBS pathway is dramatically cheaper for T2D-eligible patients. Compare your situation in our GLP-1 switch cost calculator.