Calculator
Dose-titration scheduler
Enter a starting weekly dose, target dose, step size and interval. The calculator returns a step-by-step escalation schedule and the total number of weeks to reach the target. Defaults follow the retatrutide Phase 3 ladder (1 → 12 mg in 4-week steps).
For in-vitro laboratory research planning. Not medical advice.
How retatrutide trial titration is structured
Phase 3 retatrutide trials use a slow weekly ladder: 1 mg → 2 mg → 4 mg → 8 mg → 12 mg, with 4 weeks at each step. That's a 16-week escalation phase before the maintenance window at the top dose. Slower titration is used at trial sites that report higher GI events; faster is used at sites where tolerability is good.
The ladder is not linear because GI side-effect risk scales with the percentage jump in dose, not the absolute mg. Going from 1 to 2 mg is a 100% jump, but tolerability is generally fine. Going from 8 to 12 mg is a 50% jump, but the absolute mg increase is larger and the glucagon-component effects are more noticeable. The default settings here apply a uniform step size for simplicity; real trial schedules use varied steps.
Source verified retatrutide research material
The Retatrutide pens and vials referenced in this calculator are listed on the commercial site with Janoshik COAs in the COA library.