Why won’t my Mounjaro pen turn to 1?

If the dose knob on a Mounjaro KwikPen won’t turn until 1 shows, there isn’t enough medicine left for a full dose. Each KwikPen gives 4 doses. Don’t try to use what’s left: start a new pen.

Why is my pen not clicking?

The clicks aren’t how the pen measures your dose. On a Mounjaro KwikPen, turn the knob until it stops at 1, which is one full dose, and check the window shows 0 after. The Wegovy, Ozempic and Saxenda leaflets say not to set your dose by counting the clicks: read the dose counter instead.

How long do I hold the pen in?

Mounjaro KwikPen: keep the knob pressed and slowly count to 5. Wegovy, Ozempic and Saxenda: keep pressing until the counter shows 0, then slowly count to 6 before taking the needle out.

Do I need to prime my pen every time?

The Mounjaro KwikPen is primed before every injection. Wegovy, Ozempic and Saxenda pens only need a flow check before the first injection with each new pen.

Can I count clicks to take a smaller dose?

No. The Wegovy, Ozempic and Saxenda leaflets say not to count the clicks, and the Mounjaro KwikPen gives 4 fixed doses: turning the knob until it stops at 1 gives one full dose. If you think your dose should change, talk to your prescriber.

I think I missed part of my dose. Should I inject again?

No. Don’t inject again to make up for it. On a KwikPen, if the window doesn’t show 0, put the needle back in and push the knob until it stops, without redialling the dose. Otherwise ask your prescriber or pharmacist what to do.

My Mounjaro pen has no dose knob. Is that OK?

In the UK, Mounjaro comes as the KwikPen, which has a dose knob. If your Mounjaro pen looks different, don’t use it until you’ve checked with the pharmacist who supplied it. You can report a suspected fake medicine through the Yellow Card scheme.

Pen not working?

Pick your pen and what it’s doing, and get the fix from the maker’s own leaflet. Or watch every step of an injection on a 3D pen, from fitting the needle to the final count.

Updated 31 October 2026

1. Your pen

2. What’s happening?

Loading the 3D pen…

Stop and contact your pharmacist if the pen is damaged, the medicine is cloudy, discoloured or has bits in it, it has been frozen, or it’s past its expiry date. The manufacturer’s phone number is in your pack leaflet. For urgent advice, call NHS 111.

How to use your pen, step by step

The same steps the 3D pen shows, from each pen’s UK leaflet.

▸How to use the Mounjaro KwikPen

Take off the cap. Pull the pen cap straight off. Check the medicine is clear and colourless to slightly yellow with no bits in it, and that the pen is in date.
Fit a new needle. Use a new needle every time. Screw it on straight until it’s tight, then pull off the outer needle cap (keep it) and the inner cap (throw it away). Needles aren’t in the box: ask your doctor, pharmacist or nurse which needle to use.
Prime it, every time. Slowly turn the dose knob until you hear 2 clicks and the prime line shows in the dose window. Point the needle up and tap the pen gently so any air rises. Push the knob in until it stops, then slowly count to 5 while holding it. A drop of medicine should appear at the needle tip, and the window should show 0.
Dial to 1. Turn the dose knob until it stops and 1 shows in the dose window. 1 means one full dose.
Inject. Push the needle into your skin as your instructions show, then press the dose knob all the way in.
Hold and count to 5. Keep holding the knob down and slowly count to 5. The dose window must show 0 before you take the needle out: that confirms the full dose has gone in.
Finish safely. Pull the needle straight out. A drop at the tip afterwards is normal. Carefully put the outer needle cap back on, unscrew the needle and put it in a sharps bin. Put the pen cap back on, and never share your pen.

▸How to use the Wegovy FlexTouch

Take off the cap. Pull the pen cap straight off. Check the medicine is clear and colourless with no bits in it, and that the pen is in date.
Fit a new needle. Use a new needle every time. Screw it on straight until it’s tight, then pull off the outer needle cap (keep it) and the inner cap (throw it away).
Flow check, new pen only. Only before the first injection with each new pen: turn the dose selector to the flow check symbol, hold the needle up and press the dose button until the counter shows 0. A drop should appear at the needle tip.
Dial your dose. Turn the dose selector to your prescribed dose and read it in the dose counter. Don’t set your dose by counting the clicks.
Inject. Push the needle into your skin as your leaflet shows, then press the dose button all the way in.
Hold and count to 6. Keep pressing until the counter shows 0, then slowly count to 6 before you take the needle out.
Finish safely. Pull the needle straight out. A drop at the tip afterwards is normal. Carefully put the outer needle cap back on, unscrew the needle and put it in a sharps bin. Put the pen cap back on, and never share your pen.

▸How to use the Ozempic pen

Take off the cap. Pull the pen cap straight off. Check the medicine is clear and colourless or almost colourless with no bits in it, and that the pen is in date.
Fit a new needle. Use a new needle every time. Screw it on straight until it’s tight, then pull off the outer needle cap (keep it) and the inner cap (throw it away).
Flow check, new pen only. Only before the first injection with each new pen: turn the dose selector to the flow check symbol, hold the needle up and press the dose button until the counter shows 0. A drop should appear at the needle tip.
Dial your dose. Turn the dose selector to your prescribed dose and read it in the dose counter. Don’t set your dose by counting the clicks.
Inject. Push the needle into your skin as your leaflet shows, then press the dose button all the way in.
Hold and count to 6. Keep pressing until the counter shows 0, then slowly count to 6 before you take the needle out.
Finish safely. Pull the needle straight out. A drop at the tip afterwards is normal. Carefully put the outer needle cap back on, unscrew the needle and put it in a sharps bin. Put the pen cap back on, and never share your pen.

▸How to use the Saxenda pen

Take off the cap. Pull the pen cap straight off. Check the medicine is clear and colourless or almost colourless with no bits in it, and that the pen is in date.
Fit a new needle. Use a new needle every time. Screw it on straight until it’s tight, then pull off the outer needle cap (keep it) and the inner cap (throw it away). Needles aren’t in the box: ask your doctor, pharmacist or nurse which needle to use.
Flow check, new pen only. Only before the first injection with each new pen: turn the dose selector to the flow check symbol, hold the needle up and press the dose button until the counter shows 0. A drop should appear at the needle tip.
Dial your dose. Turn the dose selector to your prescribed dose and read it in the dose counter. Don’t set your dose by counting the clicks.
Inject. Push the needle into your skin as your leaflet shows, then press the dose button all the way in.
Hold and count to 6. Keep pressing until the counter shows 0, then slowly count to 6 before you take the needle out.
Finish safely. Pull the needle straight out. A drop at the tip afterwards is normal. Carefully put the outer needle cap back on, unscrew the needle and put it in a sharps bin. Put the pen cap back on, and never share your pen.

At a glance

Pen	Air shot	Hold	Taken
Mounjaro KwikPen	Prime before every injection	Slowly count to 5	once a week
Wegovy FlexTouch	Flow check with each new pen	Slowly count to 6	once a week
Ozempic pen	Flow check with each new pen	Slowly count to 6	once a week
Saxenda pen	Flow check with each new pen	Slowly count to 6	once a day

Common questions

Why won’t my Mounjaro pen turn to 1?: If the dose knob on a Mounjaro KwikPen won’t turn until 1 shows, there isn’t enough medicine left for a full dose. Each KwikPen gives 4 doses. Don’t try to use what’s left: start a new pen.
Why is my pen not clicking?: The clicks aren’t how the pen measures your dose. On a Mounjaro KwikPen, turn the knob until it stops at 1, which is one full dose, and check the window shows 0 after. The Wegovy, Ozempic and Saxenda leaflets say not to set your dose by counting the clicks: read the dose counter instead.
How long do I hold the pen in?: Mounjaro KwikPen: keep the knob pressed and slowly count to 5. Wegovy, Ozempic and Saxenda: keep pressing until the counter shows 0, then slowly count to 6 before taking the needle out.
Do I need to prime my pen every time?: The Mounjaro KwikPen is primed before every injection. Wegovy, Ozempic and Saxenda pens only need a flow check before the first injection with each new pen.
Can I count clicks to take a smaller dose?: No. The Wegovy, Ozempic and Saxenda leaflets say not to count the clicks, and the Mounjaro KwikPen gives 4 fixed doses: turning the knob until it stops at 1 gives one full dose. If you think your dose should change, talk to your prescriber.
I think I missed part of my dose. Should I inject again?: No. Don’t inject again to make up for it. On a KwikPen, if the window doesn’t show 0, put the needle back in and push the knob until it stops, without redialling the dose. Otherwise ask your prescriber or pharmacist what to do.
My Mounjaro pen has no dose knob. Is that OK?: In the UK, Mounjaro comes as the KwikPen, which has a dose knob. If your Mounjaro pen looks different, don’t use it until you’ve checked with the pharmacist who supplied it. You can report a suspected fake medicine through the Yellow Card scheme.

Instructions from the UK patient leaflets for Mounjaro, Wegovy, Ozempic and Saxenda, and the KwikPen instructions for use.

General information to help you use your pen, not medical advice. Always follow the leaflet in your pack and your prescriber’s instructions. Report side effects through the Yellow Card scheme.

Pen not working?

How to use your pen, step by step

At a glance

Common questions

Related tools