Where do you inject Mounjaro?

Inject MOUNJARO subcutaneously in the abdomen, thigh, or another person should inject in the back of the upper arm. Rotate injection sites with each dose. That is the label's wording, not a summary of it. Nothing about the site changes the dose — the label sets no different dose for one site over another.

How long can Mounjaro stay out of the fridge?

21 days, and the label states it as a total rather than a run: If needed, each single-dose pen or single-dose vial can be stored at room temperature up to 86°F (30°C) for up to a total of 21 days. Past that the instruction is to discard, which is why this page carries a price at all — a discarded pen is $499 of medication at the maintenance rate stored here.

What syringe does a Mounjaro vial need?

Use a syringe appropriate for dose administration (e.g., a 1 mL syringe capable of measuring a 0.5 mL or 0.6 mL dose) and always use a new syringe and needle for each injection. The vial is usually the cheaper presentation, and this is the trade that comes with it: the pen measures the dose for you, the vial does not.

Where do you inject Mounjaro?

Inject MOUNJARO subcutaneously in the abdomen, thigh, or another person should inject in the back of the upper arm. Rotate injection sites with each dose. That is the label's wording, not a summary of it. Nothing about the site changes the dose — the label sets no different dose for one site over another.

How long can Mounjaro stay out of the fridge?

21 days, and the label states it as a total rather than a run: If needed, each single-dose pen or single-dose vial can be stored at room temperature up to 86°F (30°C) for up to a total of 21 days. Past that the instruction is to discard, which is why this page carries a price at all — a discarded pen is $499 of medication at the maintenance rate stored here.

What syringe does a Mounjaro vial need?

Use a syringe appropriate for dose administration (e.g., a 1 mL syringe capable of measuring a 0.5 mL or 0.6 mL dose) and always use a new syringe and needle for each injection. The vial is usually the cheaper presentation, and this is the trade that comes with it: the pen measures the dose for you, the vial does not.

How to inject Mounjaro

Taken once weekly, at any time of day, with or without meals. Everything below is quoted from the FDA label rather than summarised, because a dosing instruction restated twice stops being the label and the detail that goes missing is always the number. What this page adds to the label is the part the label has no reason to carry: what a mistake costs.

How do you inject Mounjaro, and what does getting it wrong cost?

Inject MOUNJARO subcutaneously in the abdomen, thigh, or another person should inject in the back of the upper arm. Rotate injection sites with each dose. Storage is where the money is: the label allows 21 days out of the refrigerator, counted as a total rather than a run, and past it says to discard. At the maintenance rate stored on this site that is $499 thrown away — one pen, one month. On a missed dose the label is specific rather than permissive, and the window is short — the exact wording is below.

What the label says

Where it goes

Inject MOUNJARO subcutaneously in the abdomen, thigh, or another person should inject in the back of the upper arm.

Rotating sites

Rotate injection sites with each dose.

Before use

Store each single-dose pen or single-dose vial in the refrigerator between 36°F to 46°F (2°C to 8°C).

Out of the fridge — 21 days

If needed, each single-dose pen or single-dose vial can be stored at room temperature up to 86°F (30°C) for up to a total of 21 days.

Freezing

Do not freeze MOUNJARO. Do not use MOUNJARO if frozen.

A missed dose

If a dose is missed, instruct patients to administer MOUNJARO as soon as possible within 4 days (96 hours) after the missed dose. If more than 4 days have passed, skip the missed dose and administer the next dose on the regularly scheduled day.

If you use vials

Use a syringe appropriate for dose administration (e.g., a 1 mL syringe capable of measuring a 0.5 mL or 0.6 mL dose) and always use a new syringe and needle for each injection.

Read from FDA prescribing information for MOUNJARO on 2026-08-28. Labels are revised; the date is there so you can tell how old this reading is. Information only, not medical advice — dosing is a decision for the clinician who wrote the prescription.

What a mistake costs

A pen left out past 21 days: $499. The label says discard it, and nothing about a partial refund follows — that is a month of medication at the maintenance rate this site stores for Mounjaro.
A frozen box: the same $499. The label is categorical about not using it, whatever it looks like afterwards.

What Mounjaro costs without insurance →The full Mounjaro dose schedule →

Injecting Mounjaro, answered

Where do you inject Mounjaro?: Inject MOUNJARO subcutaneously in the abdomen, thigh, or another person should inject in the back of the upper arm. Rotate injection sites with each dose. That is the label's wording, not a summary of it. Nothing about the site changes the dose — the label sets no different dose for one site over another.
How long can Mounjaro stay out of the fridge?: 21 days, and the label states it as a total rather than a run: If needed, each single-dose pen or single-dose vial can be stored at room temperature up to 86°F (30°C) for up to a total of 21 days. Past that the instruction is to discard, which is why this page carries a price at all — a discarded pen is $499 of medication at the maintenance rate stored here.
What if you miss a dose of Mounjaro?: If a dose is missed, instruct patients to administer MOUNJARO as soon as possible within 4 days (96 hours) after the missed dose. If more than 4 days have passed, skip the missed dose and administer the next dose on the regularly scheduled day.
What syringe does a Mounjaro vial need?: Use a syringe appropriate for dose administration (e.g., a 1 mL syringe capable of measuring a 0.5 mL or 0.6 mL dose) and always use a new syringe and needle for each injection. The vial is usually the cheaper presentation, and this is the trade that comes with it: the pen measures the dose for you, the vial does not.

Everything on Mounjaro

Last updated 2026-08-28 — the FDA label this page quotes