Tirzepatide research: studies, doses and safety

• Weeks 1-4: Zepbound starts at 2.5 mg weekly; nausea, diarrhea and vomiting are common during dose increases.
• Weeks 5-8: The schedule moves to 5 mg weekly, the lowest weight-management maintenance dose.
• Weeks 9-16, if increasing: Higher-dose paths use 7.5 mg and then 10 mg weekly, with at least four weeks at each dose.
• Week 17 onward, if increasing: The highest-dose path uses 12.5 mg weekly for at least four weeks before 15 mg weekly.
• Week 72: Adults without diabetes in SURMOUNT-1 averaged 15.0-20.9% weight loss across target doses versus 3.1% with placebo.

Zepbound is used weekly for long-term weight management; its main weight-loss trial lasted 72 weeks.

216 date-filtered interventional registry records name tirzepatide; 71 are completed and 46 have posted results. This is a registry inventory, not 216 completed efficacy trials.

Key studies

• First human doses: Early 0.5 mg exposure does not establish long-term wellness microdosing. (source)
• Phase 2: dose finding: Higher doses improved glucose more and caused more stomach upset. (source)
• Phase 2: three starts: Starting dose and step size affect tolerability. (source)
• Early Japanese dosing: A small trial supported weekly dosing in Japanese adults. (source)
• Early Chinese dosing: Slow escalation supported tolerability in a small Chinese study. (source)
• SURPASS-1: Glucose and weight improved without background diabetes drugs. (source)