GLP1 MathMissed a tirzepatide dose?
Zepbound and Mounjaro share the same rule on their FDA labels: a 4-day window.
The 4-day rule
- If it has been 4 days (96 hours) or less since your scheduled dose, take it as soon as you remember, then take the next dose on your regular day.
- If it has been more than 4 days, skip the missed dose and take the next one on your regular day.
- Never take two doses within 3 days (72 hours) of each other.
Compounded tirzepatide
Compounded vials carry no FDA label. Most clinics use the same 4-day rule. Confirm with the clinic that prescribed it.
Changing your injection day
You can move your weekly day as long as at least 3 days (72 hours) pass between doses. Pick the new day, keep it, and map the new dates.
Missed 2 or more weeks
Call your prescriber before restarting. Many restart one step lower (for example, back to 5 mg from 7.5 mg) because stomach side effects return when tolerance fades.
Vacation, travel, lost shipment
Same rule applies. If you are inside the 4-day window, take it; outside it, skip. Keep the vial or pen refrigerated when you can; check the label for how long it can stay at room temperature.