How-To Guides · 24 April 2026 · 10 min read

How to Inject Wegovy, Mounjaro or Ozempic: Step-by-Step Guide for UK Users

Never injected before? This step-by-step guide covers exactly where and how to inject Wegovy, Mounjaro or Ozempic — injection sites, rotation, storage, common mistakes and tips for needle anxiety.

Last updated: April 2026 | 10 min read

Starting a GLP-1 injection like Wegovy, Mounjaro or Ozempic can feel daunting if you've never injected yourself before. The good news is that these medications use very fine auto-injector pens specifically designed for self-administration — and most people find them far less scary than they expected after their first injection.

This step-by-step guide covers everything you need to know: where to inject, how to inject correctly, how to store your medication, how to rotate injection sites, and the most common mistakes to avoid. Whether you're waiting for your first pen to arrive or you've already started and want to make sure you're doing it right, this guide has you covered.

The Three Injection Sites

GLP-1 medications can be injected into three areas of the body. All three are equally effective at delivering the medication — the choice comes down to personal preference and convenience.

1. The Abdomen (stomach)

This is the most commonly used and generally easiest site. Inject into the fatty tissue at least 5cm (2 inches) away from your belly button. Avoid the area directly around the navel, as the skin is tighter and injections can be more uncomfortable there. The abdomen has plenty of subcutaneous fat even in lean individuals, which makes it a reliable choice for most people.

2. The Thigh (front or outer)

The front or outer thigh is another good option. Inject into the middle third of your thigh — roughly halfway between your knee and hip. Avoid the inner thigh (too many blood vessels nearby) and the back of the thigh. The thigh is particularly convenient if you're injecting while seated.

3. The Upper Arm (outer)

The outer part of the upper arm is the third approved site. This area can be harder to reach yourself — many people ask a partner or family member to help if they choose this site. Never inject into the inner arm or near the shoulder joint.

Step-by-Step: How to Inject Wegovy, Mounjaro or Ozempic

The exact steps vary slightly between the Wegovy FlexTouch, Mounjaro KwikPen and Ozempic pen — always read the instructions that come with your specific device. However, the general process is the same for all three.

Before you start

• Wash your hands thoroughly with soap and water and dry them completely
• Check the pen — make sure the medication is clear (not cloudy or discoloured) and the pen hasn't expired
• Remove from the fridge 30 minutes before — injecting cold medication can sting more. Let it reach room temperature first
• Gather your supplies — alcohol wipe (optional), the pen, a sharps bin for the used needle cap

Preparing the pen

• Wegovy: Remove the pen cap. Check the dose window shows the correct dose. For a new pen, you don't need to prime it — Novo Nordisk pens are pre-primed
• Mounjaro: Remove the grey base cap. Check the solution is clear. The KwikPen is ready to use — no priming required
• Ozempic: Attach a new NovoFine needle, prime the pen if it's a new one (press the dose button until a drop appears at the needle tip), then select your dose

The injection

1. Clean the area (optional) — an alcohol wipe is recommended by some clinics but not all. If you use one, let the skin dry completely before injecting — alcohol can sting if wet
2. Pinch up the skin — gently pinch a fold of skin at your chosen site using two fingers. This lifts the subcutaneous fat away from the muscle below
3. Position the pen — hold it at a 90-degree angle to your skin (straight in, not at an angle) and press the pen firmly against the pinched skin
4. Press and hold — press the injection button. For Wegovy and Mounjaro: hold the pen in place for the full count displayed on the pen (usually 10 seconds) before releasing. This ensures all the medication is delivered
5. Remove the pen — lift the pen straight away from the skin without twisting
6. Apply gentle pressure — press a clean finger or cotton ball against the site for a few seconds. Do not rub — this can spread the medication away from the injection site
7. Dispose safely — place the used pen in your sharps bin immediately. Never put used pens in household bins. Your pharmacy will usually accept sharps bins for disposal

Rotating Injection Sites

This is one of the most important things to get right and one of the most commonly overlooked. Injecting repeatedly into the same spot causes lipohypertrophy — a build-up of hardened fatty tissue under the skin. This looks like a small lump or dimple and, crucially, absorbs medication less effectively. People who develop lipohypertrophy and keep injecting into it may find their medication stops working as well as it should.

The solution is systematic rotation. Keep a rough mental map of your injection sites and move around the area. For example:

• If you use the abdomen: divide it into four quadrants (upper left, upper right, lower left, lower right) and rotate between them week by week
• If you use multiple sites: alternate between abdomen, thigh and upper arm across different weeks
• Leave at least 2–3cm between any two injection points in the same area
• Avoid any site that already has a lump, scar tissue, bruising or active skin condition

Storing Your Medication

Incorrect storage is one of the most common causes of reduced medication effectiveness — and can result in wasted, expensive pens.

Before first use (unopened pens)

• Store in the refrigerator at 2–8°C
• Keep away from the freezer compartment — frozen pens must be discarded
• Keep the pen cap on and in its original carton to protect from light

After first use (in-use pens)

• Wegovy: Store below 30°C away from direct heat and light for up to 28 days after first use. Can be kept outside the fridge
• Mounjaro: Once removed from the fridge, store below 30°C for up to 21 days. Do not refrigerate again after it's been at room temperature
• Ozempic: Once in use, store below 30°C for up to 6 weeks (42 days)

Always check the patient information leaflet inside your specific pen for the most up-to-date storage guidance.

Common Mistakes to Avoid

Injecting too quickly

Rushing the injection and not holding the pen in place for the full count is one of the most common errors. If you remove the pen before the full dose is delivered, you'll get less medication. Always count to 10 (or whatever your pen specifies) before removing.

Not rotating sites

As above — this is critical. Build a rotation system and stick to it.

Injecting into muscle instead of fat

GLP-1 medications should be injected subcutaneously (into fat), not intramuscularly. Using the pinch technique helps ensure you're targeting the right layer. If you're very lean, talk to your pharmacist — they may recommend a shorter needle length.

Injecting cold medication

Taking the pen straight from the fridge and injecting immediately is more likely to sting and cause local discomfort. Let it warm to room temperature for 20–30 minutes first.

Rubbing the injection site

After removing the pen, gently press — don't rub. Rubbing disperses the medication too quickly and can cause bruising.

Not disposing of pens properly

Used auto-injector pens are clinical waste. They must go into a sharps container, not your household bin. Most pharmacies and GP surgeries will accept sharps bins for disposal — ask your clinic when you start treatment.

What's Normal After an Injection

Some reactions at the injection site are completely normal, especially when you're new to injecting:

• Mild redness, itching or swelling — common and usually resolves within an hour or two
• Small bruise — normal, especially if you nicked a tiny blood vessel. Rotating sites helps reduce this
• Small lump — can appear if you injected a little shallow or into skin that's not fully settled. Resolves on its own
• Mild stinging during the injection — often reduced by letting the pen warm up first

Contact your clinic or pharmacist if you experience: severe pain, significant swelling that doesn't resolve, redness spreading beyond the injection site, or signs of infection (warmth, pus, fever).

Tips for Injection Anxiety

Fear of needles is extremely common — surveys suggest up to 25% of adults have some degree of needle anxiety. The good news is that GLP-1 auto-injector pens use very fine, short needles (typically 4–8mm). Most people describe the sensation as a mild pinch or nothing at all.

• Look away — you don't need to watch. Position the pen, then look away before pressing
• Distract yourself — watch something on your phone or listen to music while injecting
• Ice the area first — applying an ice pack or ice wrapped in a cloth for 30 seconds numbs the skin and significantly reduces sensation
• Breathe out slowly as you inject — releasing tension as you press the button helps
• Set a routine — same day, same time, same place. Predictability reduces anxiety
• Track your injections — apps like Lotessa let you log each injection, track how you feel, and connect with a community of people going through the same experience — which many users find genuinely reassuring
• It gets easier — most people report their anxiety reducing significantly after 2–3 injections. By week 4 or 5, it typically feels entirely routine

Frequently Asked Questions

Can I inject through clothing?
Technically possible in an emergency, but not recommended as standard practice. There's an increased risk of contamination and it makes it harder to pinch the skin properly.

What if I miss a dose?
For Wegovy and Ozempic: if you've missed by 5 days or less, inject as soon as you remember. If more than 5 days have passed, skip the missed dose and take the next one on your usual day. For Mounjaro: take it as soon as you remember if your next dose is at least 4 days away. If not, skip and resume your normal schedule. Never double dose.

Can I inject in public?
Yes — many users inject discreetly in restaurants or while out. The auto-injector pens are compact and don't require any preparation beyond removing the cap. A clean surface and clean hands are the main requirements.

What if I can't feel my injection going in?
This is fine and actually common. Some areas have fewer nerve endings. As long as you held the pen firmly in place for the full count, the medication was delivered.

My pen is making a clicking noise — is that normal?
Yes. Both Wegovy and Mounjaro pens click when the dose is complete. This is a feature to let you know the injection is done.

GLP1Guide.live does not provide medical advice. The information in this guide is for educational purposes only. Always follow the patient information leaflet that comes with your specific medication and consult your prescribing clinician if you have any concerns.