Zepbound — dual GIP/GLP-1 for chronic weight management.

Zepbound is tirzepatide, formulated and branded by Eli Lilly for chronic weight management. FDA-approved in 2023, same BMI criteria as Wegovy (≥30, or ≥27 with comorbidity). Once-weekly subcutaneous injection.

Same active molecule as Mounjaro (also tirzepatide, but FDA- approved for T2DM). Same molecule available compounded through 503A pharmacies, subject to FDA shortage status and regulatory posture.

Tirzepatide is a dual agonist — it activates both the GLP-1 receptor (like semaglutide) and the GIP receptor (glucose- dependent insulinotropic peptide). The combined activation produces stronger insulin response, additional satiety signaling, and synergistic metabolic effects beyond GLP-1-only therapy.

Clinically, that translates to greater weight loss than semaglutide at equivalent treatment duration. The SURMOUNT-1 trial showed mean 22.5% reduction at 72 weeks on the 15mg dose, compared to ~15% on semaglutide's STEP-1 trial.

Zepbound tends to fit:

• Adults with BMI ≥30, or ≥27 with comorbidity
• Patients targeting greater weight loss than semaglutide produces
• Patients with insulin resistance who benefit from the GIP component
• Patients who've plateaued on semaglutide

Six-step dose escalation: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg, once weekly, increasing every 4 weeks. Maintenance is typically 5, 10, or 15mg depending on response and tolerance.

Mean 22.5% reduction at 72 weeks on the 15mg dose (SURMOUNT-1). Side effects: nausea, constipation, diarrhea, vomiting — generally similar profile to semaglutide but slightly higher reported nausea rates during early titration. Slow titration minimizes most side effects.

Same approach as Wegovy: branded Zepbound when insurance covers it, compounded tirzepatide when the 503A pathway permits. Both prescribed through the same physician relationship. Patients sometimes start on semaglutide and transition to tirzepatide when they plateau — we'll design the transition based on labs and weight trajectory.