Mounjaro is already tirzepatide so switching at the same weekly dose is mostly just a product change. Side effects should follow what you already experience at 7.5 rather than a new titration. Heart rate discussion in studies is a class effect. Tirzepatide can raise resting heart rate a little and retatrutide trials noted it more at higher doses but that is something to watch later with retatrutide rather than during the Mounjaro to tirzepatide step.
Has anyone switched from Mounjaro to tirzepatide and later to retatrutide? I'm wondering about the side effects. I'm currently on Mounjaro at 7.5 but costs are pushing me to tirzepatide because it's less expensive. I'll stay on that until around March next year and check my progress. If things slow I was thinking of moving on but I'm worried about heart rate increases during the change.