Short answer: Weekly weight-loss injections (Mounjaro, Ozempic, Wegovy) can be taken on any day of the week, but they should be given on the same day each week; the time of day is up to you, with or without meals.

Key takeaways

  • There is no required day; you can choose the fixed day that best suits your lifestyle.
  • According to the product information, the dose day can be changed if there are at least 3 days (72 hours) between two doses with tirzepatide (Mounjaro, Zepbound) and at least 2 days (48 hours) with semaglutide (Ozempic, Wegovy).
  • According to the product information, a missed dose is taken within 4 days (96 hours) with tirzepatide (Mounjaro, Zepbound) or within 5 days with Ozempic; with Wegovy, it is taken if the next dose is more than 2 days away. Otherwise that dose is skipped and the usual day continues.
  • The product information does not provide for a double dose to make up for a missed one.

Weekly GLP-1 injections are given on the same day each week. You choose the day; the product information does not impose a specific one. The time is also up to you and does not depend on meals. The day can be changed later if needed, but there is a minimum amount of time that must be left between two injections.

This page is for general information only and does not replace medical advice. Injection day, dose and duration are decisions for your doctor alone. The package leaflet for your own medication takes priority over the general information on this page.

How to choose the day

Medically, no day is better than another. In practice, two things decide it: a day that is easy to remember, and how the day fits your schedule.

Digestive side effects can return for a few days after each dose increase, so some people prefer not to line their injection day up with a busy workday. This is not a medical recommendation.

Can you change the day?

Yes. According to the product information for tirzepatide products (Mounjaro, Zepbound), the weekly injection day can be changed when needed; the only condition is that there are at least 3 days (72 hours) between two doses. In other words, when switching to a new day, the two injections should not be less than three days apart.

The weekly day can also be changed for semaglutide products (Ozempic, Wegovy); the US product information requires at least 2 days (48 hours) between two doses. Check your own package leaflet and let your doctor know about the change.

What should I do if I miss a dose?

The answer depends on the active ingredient, and this is one of the most commonly confused points about missed doses.

  • Tirzepatide (Mounjaro, Zepbound): according to the prescribing information, the missed dose is taken within 4 days (96 hours). If more than four days have passed, that dose is skipped and the next one is taken on the usual day.
  • Ozempic (semaglutide): according to the prescribing information, the missed dose is taken within 5 days. If more than five days have passed, it is skipped and the usual schedule continues.
  • Wegovy (semaglutide): according to the US prescribing information, the missed dose is taken if the next scheduled dose is more than 2 days away. If it is 2 days away or less, it is skipped and the next dose is taken on the usual day.

The product information does not provide for taking two doses back to back to make up for a missed dose. If you have missed doses two weeks in a row, or are unsure in a specific situation, talk to your doctor.

Same day but a different time?

That is fine. With weekly products, what matters is the interval in days, not the time. Taking a dose in the morning one week and in the evening the next is not a problem, as long as the minimum time between two injections is respected.

Tracking the day

On a weekly schedule, the hardest part is not remembering the day but remembering what happened last week. Haftra sets up the plan automatically from your first dose, reminds you on your dose day and the day before, and recalculates the calendar when you change the day. It is free, can be used without an account and does not suggest doses.

iPhone, iPad and Apple Watch. Free.

Frequently asked questions

Which day should a weight-loss injection be taken?

Weekly products have no required day; you choose the day, as long as it is the same day each week. Choosing a day that is easy to remember and that fits your schedule is what usually decides it.

Can I change my injection day?

Yes. With tirzepatide products (Mounjaro, Zepbound), there must be at least 3 days (72 hours) between two doses. With semaglutide products (Ozempic, Wegovy), the US product information requires at least 2 days (48 hours). Check your package leaflet.

What should I do if I miss a dose?

According to the product information, with tirzepatide (Mounjaro, Zepbound) the missed dose is taken within 4 days (96 hours); if more than 4 days have passed, it is skipped and the next dose is taken on the usual day. With Ozempic, the window is 5 days. With Wegovy, it is taken if the next dose is more than 2 days away; otherwise it is skipped. Two doses are never taken back to back to make up, and if you missed two weeks in a row, talk to your doctor.

I delayed my dose by 2 days. What does the label say?

Two days is within the window the product information gives for tirzepatide (4 days) and Ozempic (5 days), and with Wegovy the next dose is still more than 2 days away. In that case, according to the label, the dose is taken as soon as it is remembered and the next dose continues on the usual day. If you are unsure, ask your doctor or pharmacist.

Do I have to inject at the same time every week?

No. With weekly products, what matters is the interval in days, not the time. The time is up to you and the injection does not depend on meals.

Sources

Last reviewed: October 15, 2026