Midlife Pen Palswith Lily

Lily is your AI guide.

The leaflet way, with my notes

How to use your KwikPen, step by step.

The official UK instructions in plain English, with my notes in the margin. Four doses in a pen, one a week. It feels fiddly the first time, and it soon gets quick.

This page follows the UK Instructions for Use (July 2025), and the step numbers match the ones in your box.

Lily, AI-generated, at her kitchen table with the pen leaflet and a highlighter
Highlighter at the ready

Know your pen

The parts, and what they're for

Your pen holds 4 fixed doses, one a week. The needles come separately. Tap or hover over a number.

mg 0 1 2 3 4 5 6 7 8
Drawing not to scale. Got the newer pen? It works the same way, but may look a little different.
  1. Pen cap, with a clip. Keep it on between jabs.
  2. Red inner seal. Wipe it with a swab before every jab.
  3. Cartridge holder, the clear part. Its marks are not a measuring scale. Never use them to measure a dose.
  4. Plunger. Moves forward a little with each jab.
  5. Pen body and label. Check the name and strength every time.
  6. Dose window. Shows 0, the prime line, or 1.
  7. Dose indicator. The mark the window reading lines up with.
  8. Dose knob. Turn it to dial. Push it to inject.

Reading the dose window

0Ready, and after a full push
The long linePrime position: 2 clicks
1One full dose (0.6 mL)

How many doses are left?

Look at the plunger in the clear holder. Each full dose moves it the same step towards the needle.

  1. Full pen
  2. After 1 dose
  3. After 2 doses
  4. After 3 doses
  5. After 4: it locks

The positions in this drawing are rough. After the fourth dose the pen locks, and a little liquid stays behind: that's for priming, not a fifth dose. The newer pen starts with the plunger further along and finishes almost at the tip. On a part-dose plan, each step is smaller.

The needle parts

A B C D
  1. Paper tab. Peel it off the new needle.
  2. Outer needle shield. Keep it. You'll need it to take the needle off.
  3. Inner needle shield. Bin it.
  4. Needle. A new one every jab.

Before you start

What you'll need

  • Your pen: the right name and strength, in date.
  • A new pen needle. Needles aren't in the box, so ask your pharmacy for ones that fit the KwikPen.
  • An alcohol swab.
  • Cotton wool or gauze.
  • A sharps bin. Ask your pharmacy or GP how to get one.

First jab?

Start with your tummy. The needle is tiny.

Steps 1 to 6

Get ready

  1. Wash your hands with soap and water.
  2. Pull the cap straight off and check the pen. Right name and strength, in date, not damaged. The liquid should be clear, colourless to slightly yellow. Frozen, cloudy, discoloured, or bits floating? Don't use it.
  3. Wipe the red inner seal with a swab.
  4. Take a new needle and peel off the paper tab.
  5. Push the needle straight on and twist until it's tight.
  6. Pull off the outer needle shield and keep it. Pull off the inner needle shield and bin it.

Why a new needle every time?

It helps prevent infections and blocked needles. Reusing one saves pennies and risks both.

Steps 7 to 9, every single jab

Prime the pen

Priming clears air out of the cartridge and shows the pen is working. It's a small test squirt into the air, and none of it goes into you.

  1. Turn the dose knob slowly until you hear 2 clicks and the long line shows in the window. That's the prime position. Gone past it? Turn either way to line it back up.
  2. Hold the pen needle up. Tap the clear holder gently so any air bubbles rise to the top.
  3. Push the knob in until it stops, and hold it while you count slowly to 5. The window should show 0, and a small drop should appear at the needle tip. That drop means you're primed. Don't inject this bit.

No drop?

Repeat steps 7 to 9, up to 2 more times. Still nothing? Change the needle and try once more. Still nothing? Stop, and ask your pharmacist. The instructions in your box also give Eli Lilly UK's number.

0 click click hold for 5 a drop
  1. Dial 2 clicks: the long line
  2. Needle up, tap the bubbles up
  3. Push, hold for 5, watch for a drop

Every jab, even a small one

Priming is the step that's easy to skip when you're in a rush. It uses a little liquid, and the Swiss medicines regulator says never more than 8 primes per pen in total, so there's enough left for your doses.

Steps 10 to 13

Dial and inject

  1. Pick your spot. Tummy, at least 5cm (2 inches) from your belly button, or your thigh. The back of your upper arm works too, but only if someone else does it. Use a different spot each week. The same area is fine.
  2. Turn the dose knob until it stops and 1 shows in the window. 1 means one full dose (0.6 mL).
  3. Needle into your skin. Push the knob in until it stops, then keep holding while you count slowly to 5. Check the window shows 0 before you pull out.
  4. Pull the needle out. A drop on the tip is normal and doesn't affect your dose. 0 in the window means you've had the full dose.
0 1
  1. Turn until it stops: 1 shows
  2. Needle in, push the knob all the way
  3. Hold for 5: 0 means a full dose

Where to inject

Front Back
  • You can do these yourself: tummy (keep 5cm clear of your belly button) and thighs
  • Back of the upper arms: only if someone else does it

Window not showing 0?

Put the needle back in and finish the push. Don't redial, and don't do the jab again. Still not sure you got it all? Don't top up. Ask your pharmacist before your next dose.

On a part-dose plan?

Your prescriber may have you dial a set number of clicks instead of turning to 1. Write the number on the box. The figure passed around online is about 60 clicks for a full dose, but Eli Lilly doesn't confirm it and says not to count clicks. The full click maths, and the traps, are in the free cheat sheet.

Steps 14 to 17

After your jab

  1. A spot of blood? Press lightly with cotton wool or gauze. Don't rub.
  2. Carefully put the outer needle shield back on.
  3. Unscrew the capped needle and put it straight in your sharps bin. Never leave the needle on the pen: it can leak, block, and let air in.
  4. Put the pen cap back on.

Write it on the box

Write the date the day you first use a pen, then jot down each jab. It's the easiest way to keep track of the 30 days, and of your primes.

Fridge or cupboard

Storing your pen

  • Unopened pens: in the fridge, 2°C to 8°C, until the expiry date. Never frozen. If it has frozen, bin it.
  • Once opened: fridge, or room temperature up to 30°C. Away from heat, and out of sight and reach of children.
  • Bin the pen 30 days after you first use it, or after 4 doses, whichever comes first. The fridge doesn't restart the clock.
  • Used needles go straight into a sharps bin, never loose in the household bin. Don't recycle the sharps bin. Ask your pharmacy how to get rid of a finished pen.

Making a pen last past 30 days?

Plenty of women do, to make the money work. The trade, and how careful people lower the risk, is question 3 in the free cheat sheet.

It happens

When something goes wrong

The cap won't come offTwist it gently back and forth, then pull it straight off.
The knob won't turn as far as 1Bin the pen, including what's left. There may not be enough for a full dose. Don't try to inject the leftover.
The knob is hard to pushPush more slowly. The needle may be blocked, so fit a new one and prime again. Dust, food or liquid inside the pen? Bin it and use a new pen.
Jammed, short of doses, or it arrived openedDon't try to fix it. Photograph the pen and box with the batch number showing, ring the pharmacy that supplied it, ask a pharmacist before your next dose, and report it on Yellow Card.
A new pen looks emptier than the last oneUsually that's the redesigned pen, which leaves less liquid behind. It works the same way. See how many doses are left.

For the fridge door

The 60-second version, plus 20 questions women ask online

The free cheat sheet: clicks, the 30 days, HRT and the pill, side effects in women, and what to ask your prescriber.

Get the free cheat sheet

Sources: UK Instructions for Use, Mounjaro KwikPen (July 2025) · UK patient leaflet · UK SmPC · Eli Lilly UK: modified KwikPen · Swissmedic KwikPen letter, July 2026 · Eli Lilly: don't count clicks · MHRA Yellow Card · Eli Lilly Canada: KwikPen video (the same pen and steps, but the phone number and bin advice in it are Canadian: in the UK, follow the leaflet in your box). The drawings were made for this page and are not to scale. KwikPen is a trademark of Eli Lilly and Company.