Mounjaro Injections
In stock
from £139.00
Mounjaro Injection Sites
The weight loss treatment Mounjaro is an injectable pen that can be taken at home. The active ingredient, tirzepatide, used once a week can help you lose up to 22.5% of your weight after 72 weeks on the highest maintenance dose (15mg).
While Mounjaro is proven to be an effective treatment, self-injecting can be a worrying thought for some people. Luckily, Mounjaro pens are made to make the process as simple and painless as possible.
This guide will discuss how to safely inject Mounjaro and which injection sites are best to use, so you can confidently take your medication.
Medically reviewed by
Dr Zoe MillerLast reviewed: 20 Nov 2024
How to inject Mounjaro
Mounjaro is a ‘KwikPen’ which comes pre-filled at the correct dosage, with 4 doses per pen. You inject Mounjaro once per week, at the same time and day each week. This means 1 Mounjaro pen, regardless of the dose, will last you 4 weeks. You’ll just need to attach a new small needle to the pen when it’s time for your weekly dose.
How to inject Mounjaro: a step-by-step guide
Prepare:
- Clean your hands with soap and water.
- Remove the pen from any outer packaging and check the expiration date, dose, and that there’s no sign of damage. The liquid should not be cloudy, discoloured, or have floating particles (except air bubbles which can be removed in the priming stage).
- Wipe the red inner seal with a swab.
- Attach a new needle to the pen by pushing the needle on and twisting it tight, keeping the outer cap on to avoid injury. Make sure the needle is sealed and undamaged.
- Choose your injection site – we recommend the abdomen (stomach) or upper legs (thigh), but you can use the back of your upper arm with help. Clean it with a sterile wipe or soap and water if you haven’t already.
Prime:
- Remove the outer needle cap and put it safely beside you for after the injection. Remove the inner needle shield and throw it away. Turn the dose knob at the bottom of the pen until you hear 2 clicks. This puts the pen in priming mode.
- Prime the pen by holding it with the needle pointing up. Tap the cartridge gently if you can see any air bubbles that need to come to the surface. Press down on the dose knob until it stops, hold it down and count to 5 slowly. A small amount of medicine should come out – don’t inject this dose into your body.
Inject:
- Adjust the dose knob to ‘1’.
- Insert the needle into your skin, keeping the dose counter visible and avoiding any veins or muscles. You don’t need to pinch your skin to do this. Press down on the dose knob and count slowly to 5. You should see the dose count move to ‘0’. There’s also a small click when the dose has been injected.
- Remove the needle from your skin and place the outer cap back on so you can dispose of it safely in a sharps bin.
- Replace the pen cap and store it back in the refrigerator, or a safe place away from sunlight and children. Remove the needle before storage.
"Mounjaro pens have been created to make self-injecting as comfortable and simple as possible. You won’t need to draw up the medication as the pen contains 4 pre-filled doses. There aren’t any large syringes involved either – you’ll use small needles that inject just below the skin. This makes it easy to inject into the right place, as long as you follow the instructions from your doctor and on the patient information leaflet."
Dr Zoe Miller
Medical Editor
Accreditations: MBChB, BSc
Accreditations: MBChB, BSc
What dose of Mounjaro do I inject?
Always check your dose against your dosage plan and prescription if you’ve ordered several doses at once. You must follow the dosage plan or you could put yourself at risk of serious or more severe side effects.
When you first start taking Mounjaro, your dose will be increased slowly from 2.5mg to a maximum maintenance dose of 15mg. You can also stay on lower doses of 5mg or 10mg if you’re happy with how your treatment is going or you get side effects on a higher dose.
Find out more information about the standard Mounjaro dosage plan.
What’s the best Mounjaro injection site?
The best Mounjaro injection sites are your abdomen, thigh, or the back of your upper arm. Mounjaro is a subcutaneous injection. This means it should be injected into the fatty tissues just beneath the skin. We recommend the abdomen or thigh for this reason.
Whatever injection site you use, divide it up into 4 sections and choose a new site every week, including switching between the left and right side of your body. You can also switch between injection sites, such as using your abdomen one week and your upper legs the next.
Injecting Mounjaro should never be very painful. It might hurt a bit when you administer the injection, but this should feel more like a sharp pinch and should start feeling better within a few seconds to a few minutes.
Pros and cons of each Mounjaro injection site
A study on the 5mg maintenance dose found that injecting into the abdomen led to the highest concentration of tirzepatide in the bloodstream. However, the study also found that more people reported side effects when injecting here.
This Mounjaro injection site pros and cons table compares each injection site to help you choose the best place for you:
| Abdomen | Upper leg | Upper arm |
| ✓ Fatty area of skin, making it easier to inject in the right place and usually less painful | ✓ Fatty area of skin, making it easier to inject in the right place and usually less painful | ✗Usually a less fatty area of skin than the other sites so may be more painful |
| ✓ Large surface area, making it easier to inject into a different place every week | ✓ Large surface area, making it easier to inject into a different place every week | ✗ Smaller surface area |
| ✓ Easy to reach and see | ✓ Easy to reach and see | ✗ Not easy to reach and see, unless someone is helping you |
| ✓ Can be injected with help or on own | ✓ Can be injected with help or on own | ✗ Can only be injected with help |
“The only way to know which injection site is best for you is to try them out. We recommend using your abdomen first, but if you find it difficult to inject here or cannot see what you’re doing, try your upper legs. Sit or lay down and make sure you’ve eaten if you feel faint or anxious about self-injecting. If you struggle to inject yourself, you can get someone to help but they must read the instructions for use first. Only inject into your upper arms with the help of someone else.”
Dr Zoe Miller
Medical Editor
Accreditations: MBChB, BSc
Accreditations: MBChB, BSc
How often should I rotate injection sites?
You should rotate injection sites every week. If you find that one area works best for you, such as the abdomen, there’s no need to change to a different area of the body, only the part of the skin that you inject.
Break the injection site into 4 smaller areas and use a different section every week. If it helps you to remember, write down which section you injected into each week. Make sure there’s always a finger width distance between where you injected last week and where you inject this week. Not rotating your injection site can increase the risk of injection site reactions or pain.
How to inject Mounjaro comfortably
Bring it to room temperature
If you store Mounjaro in the refrigerator, bring it to room temperature for around 30 to 60 minutes before injecting it. This can make it less painful compared to injecting it straight from the fridge due to the temperature of the liquid.
Use an ice pack or cold compress
Apply an ice pack for around 15 minutes before you inject Mounjaro. This will numb the area to make it less painful. Use a cold compress after injecting to reduce soreness or swelling.
Find the best injection site for you
You can use the same site the whole time you inject Mounjaro as long as you’re using a different area of skin each time.
As long as they’ve read all the information, you can get someone to give you the injection in any of the sites we’ve mentioned, not just your upper arms.
Use over-the-counter medications
Take an over-the-counter painkiller like ibuprofen or paracetamol before you take the injection. This gives it time to kick in and help with any pain or discomfort. If you still have mild pain for a few hours or days after the injection, you can continue using painkillers to help.
You could also get an over-the-counter numbing cream to apply before injecting Mounjaro. This can also help if you’re nervous about the injection.
Reducing anxiety around injections
If you have anxiety with needles or injections, make sure you do it in a private and comfortable environment, lie down, and have someone help or support you. If you find it difficult to relax your body, this could make the injection more painful.
Try a distraction technique, such as talking about something you like with the person helping or supporting you, or a breathing exercise to help you relax. Speak to your doctor if you’re finding injections very stressful because of your anxiety.
Follow the manufacturer's and your doctor's instructions to comfortably and safely inject Mounjaro. Familiarise yourself with the pen and how it works before your first injection. If you struggle with needles or injections, it’s best to get someone to help you or consider a weight loss tablet instead.
When’s the best time to inject Mounjaro?
There is no best time to inject Mounjaro, but it should be given at the same time and day every week. Consistency is most important when taking Mounjaro. By injecting Mounjaro at the same time and day each week, the concentration of tirzepatide in your body will remain steady – this can improve its effectiveness and reduce side effects.
You can inject Mounjaro before, after, or with food. If you get certain side effects like nausea or stomach pain, it may be best to eat a meal around an hour before injecting it. Choose a suitable time and day that works around your schedule. If you’re injecting with help from someone else, make sure this schedule also works for them.
How do I know if I injected Mounjaro correctly?
There are a few things to look for that will tell you whether you’ve injected Mounjaro correctly:
- When you watch the dose counter, it should turn from ‘1’ to ‘0’.
- The pen will click when the dose has been injected, but this is a small click and may not be heard in a loud environment.
- There should be no significant leakage from the injection site. It shouldn’t feel wet, but it’s normal if there’s a very small amount of medicine on the needle tip when you take it out.
- You shouldn’t feel severe pain when injecting Mounjaro. It may feel like a sharp sting, but this should start improving within a few seconds to a few minutes. If you have severe pain that isn’t going away after the injection, or you have any other severe reactions like a widespread rash that does not go away, or difficulty breathing, you should call 999 or go to A&E.
To help you know whether you’ve injected Mounjaro correctly, especially the first few times you use it, ask someone to watch you do it, like a partner, or friend, or ask at your pharmacy. If the needle is in your skin and you hold the dose counter down and count to 5 slowly, the injection will be complete. It’s very important to wait for the count of 5 so all the medicine goes into your body.
As you continue taking Mounjaro, you’ll start to know what it feels like when the needle is in your skin and when the injection is done.
Signs the injection didn’t work
If you don’t think you put the needle into your skin or you pulled it out too early, you might notice the dose counter didn’t reach ‘0’, or that the liquid is on your skin or has leaked out. In this case, you should speak to your doctor.
If you injected at least some of the medication, you may need to wait until your next dose. If you are confident you didn’t inject any and that the needle didn’t go into your skin, they may recommend doing the injection again.
If your Mounjaro pen doesn’t seem to be working, speak to your doctor or a pharmacist who can check the pen for you. If you have any issues with your Mounjaro pen or needles and you’re a ZAVA patient, reach out to our Patient Care team via your online account.
Reactions from injecting Mounjaro
It’s important to monitor any reactions when injecting Mounjaro and speak to your doctor if they are ongoing or severe.
Don’t choose an injection site that has sore, broken, or irritated skin.
Common
A common Mounjaro side effect that may affect 1 in 10 people is an injection site reaction, such as the site getting itchy, red, sore, or swollen. This might happen when you first start using the injection, or if you forget to switch injection sites every week.
These reactions are usually mild and temporary but speak with your doctor if this happens after every injection, even after switching areas of the skin and injection sites. They might recommend taking an antihistamine when you inject Mounjaro.
Uncommon
An uncommon Mounjaro side effect that may affect up to 1 in 100 people is injection site pain. While it’s normal to feel slight pain, stinging, or discomfort, it’s not normal for it to be very painful to inject Mounjaro.
If you find the injection site painful and this can’t be managed by a cold compress and over-the-counter pain medication, speak to your doctor straight away.
Sources
A Study of Tirzepatide at Different Injection Sites in Participants With Different Body Sizes, National Library of Medicine (accessed 07 October 2024)
How to use Mounjaro, Eli Lilly and Company (accessed 07 October 2024)
Mounjaro KwikPen 10mg solution for injection in pre-filled pen (SmPC), emc (accessed 07 October 2024)
Mounjaro KwikPen 10mg solution for injection in pre-filled pen (Patient Information Leaflet), emc (accessed 07 October 2024)
Weight loss efficiency and safety of tirzepatide: A Systematic review, National Library of Medicine (accessed 07 October 2024)
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