Mounjaro 3.75mg Clicks: Counting and Dialling Your Dose Correctly

Step 1: Prepare your pen and check the basics before you start

Take your Mounjaro KwikPen out of the fridge and let it sit at room temperature for around 30 minutes. Injecting cold solution straight from the fridge can make the injection more uncomfortable than it needs to be. While you wait, wash your hands thoroughly.

Check the pen's label confirms the correct strength, the 3.75mg pen should match what your prescriber specified. Then look through the clear window: the liquid should appear colourless to slightly yellow and free of visible particles. If it looks cloudy or contains floating matter, do not use it and contact your prescriber or reach our support team for guidance.

Attach a new needle by peeling the paper tab, pushing the needle cap straight onto the pen tip and twisting clockwise until it seats firmly. A practical checking habit worth building: once the needle is on, hold the pen up to the light and confirm the green indicator is still at the start position before you dial anything. Takes under a minute and confirms you have not accidentally pressed the button during setup.

Clean your chosen injection site (abdomen, thigh or upper arm) with an alcohol swab and let it dry. Rotate sites each week to avoid tissue changes at any one spot.

Step 2: Understand what the click count means at 3.75mg

The Mounjaro KwikPen does not have a traditional dial you twist to a number. Instead, you press and hold the injection button continuously until the device stops, the mechanism counts the dose for you. The audible and tactile clicks during injection are the pen advancing the plunger; the sequence ends when the button cannot travel further.

Because different strengths use different pen cartridges, the number of clicks you hear at 3.75mg differs from the count at 2.5mg or 5mg. Our guide to Mounjaro KwikPen clicks covers how the count maps across doses, and the clicks reference chart gives you a quick visual check for your specific pen.

The golden rule: never stop pressing early because you think you have heard enough clicks. Hold the button down until it stops moving, then keep the pen held in place against your skin for a slow count of ten. This pause ensures the full volume is delivered before you withdraw. The NHS's patient-level guidance on tirzepatide use and technique reinforces this hold step.

If you are uncertain whether your count was complete, do not re-inject. Check the green window: if it has advanced to show a new dose position, the injection is done. If it has not moved, speak to your prescriber before attempting again.

Step 3: Complete the injection and dispose safely

With the needle inserted at roughly a 90-degree angle (or 45 degrees if the site is lean), press the button firmly and hold it. You will feel resistance give way as the mechanism engages. Keep steady pressure throughout the click sequence, then maintain contact for ten seconds after the clicking stops.

Withdraw the needle smoothly. A small drop of blood or clear fluid at the site is normal. Press gently with a cotton pad if needed, do not rub. The pen's needle shield recaps automatically on most KwikPen formats once the injection button is fully depressed; check your PIL for your specific pen's needle-removal instructions.

Remove the needle immediately after each injection, never store the pen with a needle attached, and place used needles in an approved sharps container. Local councils provide free sharps collection, your pharmacist can advise on your nearest scheme.

Store the used pen back in the fridge (2–8°C) with the cap on and the needle removed. Each pen holds four doses, so after four weekly injections it is empty. For a full breakdown of what happens across a pen's four doses and how to track them, see the overview of full-pen click counts.

What to do if something feels wrong

Injection-site redness, minor bruising or temporary itching are common and usually settle within a day or two. Gastrointestinal effects (nausea, loose stools, indigestion) are the most frequently reported side effects with tirzepatide, typically most noticeable in the days following a new dose or dose change, and often ease with time. Eating smaller, lower-fat meals around injection day can help. The injection technique and side effects page covers this in more detail.

Seek urgent medical attention for any severe or persistent abdominal pain that spreads to your back: this may indicate pancreatitis, and the MHRA flagged it as a known but infrequent serious risk for GLP-1 medicines in a January 2026 Drug Safety Update. Other symptoms warranting prompt medical contact include signs of a severe allergic reaction, dehydration from prolonged vomiting, or any symptom your prescriber told you to watch for specifically.

Never adjust your dose on your own, if 3.75mg feels too strong or is not producing the response you expected, that is a conversation for your prescriber. If you are exploring what tirzepatide involves more broadly, the Mounjaro overview covers the full picture, and our treatment page is where you can speak to our prescribers about your own situation.