How to Get Excess Mounjaro Out of the Pen (October 2026)

01 · The short answer

Should you try to get the excess out of a Mounjaro pen?

No. The KwikPen is a pre-filled pen designed to deliver four weekly doses, and the dose is set by turning the dial until the correct number shows in the window.¹

Pulling liquid out with a syringe, or opening the pen, takes you outside what the pen was designed and tested to do. You cannot verify how much you have drawn or whether it is clean, and the pen is not designed for it.

No regulated UK pharmacy or prescriber can endorse it. For related questions see getting the rest out of a pen and what happens to the remainder.

02 · What to do instead

What to do instead of extracting excess

Use your four weekly doses, then discard the pen in a sharps bin. Needles, a sharps bin and injection guidance are included with every order from us. If you are worried that you did not receive a full dose, or that a pen feels wrong, contact the pharmacy or your prescriber rather than trying to fix it yourself.

If you feel you are short on medicine, the answer is a conversation, not a workaround. If you need your next pen, the Mounjaro pen starts at £169.99 per month for the 2.5mg strength, and all six doses are in stock. Prices checked 10 October 2026.

Related guide: Buy Mounjaro.

Related guide: How to get medicine out of mounjaro pen.

03 · Pen dial and clicks

How the dial works, and why clicks do not matter

You set the Mounjaro KwikPen by turning the dose knob until the dose indicator shows the correct dose in the window.

Each pen is one strength, and the number in the window is the check, never the number of clicks.

04 · Microdosing and stretching

Is microdosing or stretching a pen safe?

No. Altering doses outside the licence means unknown dosing accuracy and no safety data.

If side effects are the worry, the licensed route already exists. Everyone starts on 2.5mg weekly, and the dose can rise after at least 4 weeks in 2.5mg steps up to a maximum of 15mg, at the pace that suits you.¹ Higher is not automatically better, and many people settle at 5mg, 10mg or 15mg.

05 · If you missed priming

I forgot to prime my pen. What now?

Check the pen's instructions in the patient information leaflet, and contact the pharmacy or your prescriber if you are unsure.¹³

Do not try to "top up" a missed or doubtful injection by taking extra from the same pen. If you think a dose was incomplete, the missed-dose rule is the reference point: take a missed dose as soon as you can within 4 days (96 hours) of the scheduled time. After more than 4 days, skip it and take the next one on your usual day, and never take two doses within 3 days of each other.¹ Ask the pharmacy whether your situation counts as a missed dose.

06 · Storage and in-use life

Storage: how long can a pen be used?

Keep Mounjaro pens in a fridge at 2–8°C and never freeze them. Once in use, a pen can be kept out of the fridge not above 30°C for up to 30 days, after which it should be discarded.¹³ Keep the cap on to protect the pen from light, and never use a pen that has been frozen.

This is why a pen with liquid left in it is still discarded once your four doses are done, or after 30 days (not above 30°C) in use. Liquid remaining is not a reason to keep using it past that point. Unopened pens keep until the expiry date printed on the box, as long as they are stored in the fridge. If an unopened pen has been out of the fridge, check with the pharmacy before using it.

07 · Planning your supply

Planning supply so you never feel short

Each pen holds four weekly doses, so a pen lasts four weeks. Because every pen is one strength, a dose change means a different pen, not a different number of clicks.

If you want a regulated supply, our Mounjaro ordering page has all six strengths, sourced from Eli Lilly's UK distribution through official LillyDirect supply. Ordering works in three steps:

• Complete the free online consultation, a short health questionnaire with no obligation, through our free consultation.
• A GPhC-registered prescriber reviews it. Payment is taken when you place the order; if the prescriber decides the treatment is not suitable, the order is refunded automatically in full.
• We dispense and dispatch. Same-day dispatch applies when ordered by 3pm, with free next-day tracked delivery in temperature-controlled packaging.

New customers save £40 on their first order with code FIRST40, and an automatic £25 reorder discount applies to every future order (code DOSE25). Mounjaro is a prescription-only medicine, so every supply follows a consultation. You can also browse all weight loss treatments.