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Your First Mounjaro Injection: A Simple How-to Guide
Starting Mounjaro for the first time can feel a little daunting, especially if you have never given yourself an injection before. The good news is that the process is quick, straightforward, and gets easier with practice. At REX Pharmacy, we want you to feel confident and prepared before you begin, so we have put together this simple step by step guide to your first dose.
If you have any questions before you start, our team is always happy to talk you through it.
Quick Answer
Mounjaro is given as a once-weekly injection using a pre-filled pen, so there are no needles to attach or doses to measure yourself. Most people find the injection quick and easy once they understand the steps.
- Injected once a week, on the same day each week
- Given under the skin, usually in the stomach, thigh, or upper arm
- The pen is single-use and pre-filled with your prescribed dose
- A pharmacist can talk you through your first injection if you would like support
Before You Begin
A little preparation makes the whole process much smoother. Before your first injection, check the following:
- Check the expiry date on the pen and make sure it has been stored correctly
- Take the pen out of the fridge around 30 minutes before use, so it reaches room temperature
- Wash your hands thoroughly with soap and water
- Choose a clean, flat surface to lay out your equipment
- Have an alcohol wipe and a sharps bin ready nearby
Choosing an Injection Site
Mounjaro is injected subcutaneously, meaning into the fatty layer just under the skin. Rotating your injection site each week helps to reduce soreness and irritation.
- Front of the thigh
- Abdomen, avoiding a two-inch circle around the belly button
- Back of the upper arm, if someone else is giving the injection for you
- Avoid areas that are bruised, red, swollen, or scarred
Step by Step: Giving Your Injection
- Clean the chosen area of skin with an alcohol wipe and let it air dry
- Remove the pen cap, taking care not to touch the needle
- Pinch the skin gently and place the pen against it at a right angle
- Press the pen firmly against your skin until you hear a click, this starts the injection
- Continue holding the pen in place for around 10 seconds, or until a second click confirms the dose is complete
- Remove the pen and dispose of it safely in your sharps bin
Once the injection is complete, there is no need to rub the area. A little redness or a small bruise is common and usually settles quickly.
After Your Injection
Most people carry on with their day as normal straight after injecting. It is worth keeping a note of the date and site you used, so you remember to rotate next week.
- Note the date and time in a diary or phone reminder
- Keep track of which site you used to help with rotation
- Watch for mild side effects such as nausea or an upset stomach in the first few days
- Contact your pharmacist if you notice severe pain, swelling, or signs of an allergic reaction
Storing Your Mounjaro Pen
- Store unused pens in the fridge, between 2°C and 8°C
- A pen can be kept at room temperature for up to 21 days once removed from the fridge
- Never freeze your Mounjaro pen
- Keep the pen in its original box, away from direct light
Frequently Asked Questions
Does the injection hurt?
Most people describe it as a quick pinch rather than pain. The needle is fine and short, and many people find later injections easier once they know what to expect.
What if I forget my injection day?
If you miss a dose, contact your pharmacist for advice, as timing depends on how many days have passed. Do not double up doses without guidance.
Can someone else give me the injection?
Yes, a partner, friend, or carer can be shown how to give the injection, particularly if it is being given in the upper arm.
What should I do with used pens?
Used pens should always go into a proper sharps bin, never into household rubbish. Your pharmacy can advise on safe disposal.
What if injections aren’t right for me?
Read about the newly approved Wegovy Pill here.
Feeling Ready to Start?
Your first injection is often the hardest one, and it gets easier from there. If you would like a pharmacist to talk you through your options and the weight loss process before you begin, or if you have any concerns at all, we are here to help every step of the way.
- Preparation and site rotation reduce discomfort
- The pen does the hard work, you just need to place and press
- Keep track of your injection days and sites
- Reach out to your pharmacist with any questions
You can also get in touch if you have any questions before your first dose.
