What Is Tirzepatide?
Tirzepatide is a once-weekly injectable peptide that activates two receptors simultaneously: GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide). This dual mechanism is what distinguishes it from semaglutide, which targets GLP-1 alone.
It was FDA-approved under the brand name Mounjaro for type 2 diabetes in 2022, and as Zepbound for chronic weight management in 2023. Compounded versions are available from Tennessee-licensed pharmacies when brand product is on the FDA shortage list.
Clinical Results
The SURMOUNT-1 trial enrolled 2,539 adults with obesity (no diabetes). At 72 weeks:
5mg weekly
−15% body weight
vs. 2.4% placebo
10mg weekly
−19.5% body weight
average
15mg weekly
−20.9% body weight
highest dose
Source: Jastreboff et al., NEJM 2022. Results in patients without diabetes on 15mg/week at 72 weeks.
Tirzepatide vs. Semaglutide
| Tirzepatide | Semaglutide | |
|---|---|---|
| Receptor targets | GLP-1 + GIP | GLP-1 only |
| Max trial weight loss | ~21% | ~15% |
| Dosing frequency | Once weekly | Once weekly |
| FDA approval | Mounjaro / Zepbound | Ozempic / Wegovy |
| Compounded cost (TN) | $200–400/mo | $150–350/mo |
Dosing Protocol
Standard titration schedule used in clinical practice:
- Weeks 1–4: 2.5mg once weekly (starting dose, GI adjustment)
- Weeks 5–8: 5mg once weekly
- Weeks 9–12: 7.5mg (if needed)
- Weeks 13+: Titrate to 10mg, 12.5mg, or 15mg based on tolerance and response
Your physician may adjust this schedule. Slower titration reduces nausea significantly — do not rush dose escalation.
Cost in Tennessee
Compounded tirzepatide runs $200–400/month from a Tennessee-licensed pharmacy, depending on dose. Brand Mounjaro/Zepbound, if covered by insurance, can reduce out-of-pocket costs substantially. Consultation fees are $99–199. See our full cost guide.