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Mounjaro® Injectable Pen

Effective GLP-1 weight loss treatment

30,000+ service reviews
Mounjaro® Injectable Pen 5mg
  • check_circle_filledLose up to 20% body weight
  • check_circle_filledWeekly self-injection pens
  • check_circle_filledSupports healthy weight loss by reducing appetite and making your feel fuller
  • check_circle_filledNo subscriptions, lowest price guarantee
£149.99for 1 pen (4 doses)

After answering some quick health questions, we’ll recommend suitable treatments for you.

Dr Clare Morrison, Consultant GP

Weight loss that’s 6× more effective

Illustration of weight loss using GLP-1 injectable treatments showing it is 6 times more effective than diet alone

Mounjaro® information

Mounjaro® KwikPen (tirzepatide) is an innovative injectable weight loss drug. It mimics natural GLP-1 and GIP hormones in your gut, helping you control your appetite and making you feel fuller for longer. When paired with a reduced-calorie diet and increased physical activity, it results in effective, healthy weight loss.
Mounjaro® is an injectable medication that comes in a pre-filled pen. It needs to be used once weekly, on the same day. The pen itself is simple to use and the needles are very small, so it’s relatively pain-free and easy to get used to.
Mounjaro® can be injected in the abdomen, thigh or upper arm at any time during the day, with or without food. It’s recommended that you use it around the same time each week — this will regulate the medication’s effectiveness.
You’ll receive clear instructions with your first order on the specifics for applying your treatment confidently. Our team are also on hand to answer any questions.
Mounjaro® (tirzepatide) is an injectable weight loss drug for people with a BMI over 30. For individuals with weight related health concerns, they may be eligible with a BMI over 27. These related concerns include high blood pressure, diabetes, heart disease and raised cholesterol.
If you have Type 2 diabetes and a BMI less than 27, we can’t prescribe you Mounjaro® for weight loss.
Your treatment starts at a low dose and then increases every four weeks. When you first start using Mounjaro®, the starting dose is 2.5 mg, once a week, for four weeks. The dose will then be increased after every four weeks until you reach the recommended dose of 15 mg a week.
This chart shows how your dosage will increase over five months:
Mounjaro® dosage guide
The clinical team will review your weight with every order to ensure this product is working for you. This way we can ensure the dose which you peak at is optimal for you. At this peak, for us to continue prescribing Mounjaro® to you, you’ll need to have lost around 5% of your initial body weight after a period of time.
Mounjaro® is one of the most effective weight loss treatments available. On average, people lose 20.9% body weight over 36 weeks and 25.3% body weight over 88 weeks.
In a study of people with type 2 diabetes on metformin, the active ingredient in Mounjaro® was shown to be twice as effective as Wegovy and Ozempic.
When you order Mounjaro® for the first time, you’ll receive 1 pen that includes each of your 4 doses for your first 28 days of treatment. It’s important to store it in a refrigerator between 2-8°C. Mounjaro® comes in a single-dose pen that requires no mixing. You’ll also receive:
  • A sharps bin with your first order
  • 4 needles (One to use for every time you inject)
  • Swabs to clean your skin before injecting
  • An instruction leaflet
  • Extra tips to help you lose weight
With each new order, you’ll receive your next pen at the right strength for you.
When you’ve been using Mounjaro® for 3 weeks, it’s time to think about ordering your next pen from us. At this time, we’ll send you a reminder to log on and complete a weight loss consultation.
If you’re responding well to treatment, at the next order you can increase your dose. We’ll then send you an additional pen in a temperature-controlled delivery packaging. It’s important to store these in a refrigerator between 2–8°C. This pack will last you 28 days. After you finish your 3rd pen, remember to return to MedExpress to reorder supplies so you can continue treatment uninterrupted.
The clinical team will review your weight with every order to ensure this product is working for you. When you’ve used your highest tolerated dose for 6 months, we’ll review your progress. For us to continue prescribing Mounjaro® to you, you’ll need to have lost around 5% of your initial body weight.
Your health and wellbeing are our top priority, so please reach out to the MedExpress clinical team if you have any concerns while taking Mounjaro.
You’ll receive a sharps bin with your first order. This is a special waste bin that’s used to store sharps material, like needles, until it can be safely disposed of.
After every use, dispose of the needle into the sharps bin. After the 4 doses, and once the needle has been removed, the pen can be disposed of in your household waste or the sharps bin. When full, your sharps bin can be collected for disposal by your local council.
Once you’ve started treatment, you’ll be able to purchase more sharps bins with new orders.
Mounjaro® can be kept unrefrigerated for up to 21 days. However, we recommend you return the pen to the fridge after each use.
For some people, Mounjaro® can cause side effects, including nausea, vomiting, constipation and diarrhoea. They usually settle after a few weeks of medication.
To reduce the side effects, our clinicians will gradually increase your dose every four weeks, giving your body time to adjust to each treatment strength. You can also take measures such as getting fresh air, sipping cold drinks, and eating smaller, regular meals.
Uncommon side effects, affecting 1 in 100 people, may involve an increase in the risk of gallstone disease, pancreatitis, low blood sugar (hypoglycemia), and severe allergic reactions like anaphylaxis. Although these are uncommon, If you have diabetic retinopathy, you might also notice changes in your vision after starting Mounjaro®.
Rare side effects, affecting 1 in 100 people, include kidney-related issues, such as reduced function and failure, with signs like a metallic taste, reduced urine volume, and easy bruising.
‍While serious side effects are rare, they may include allergic reactions or pancreatitis. Immediate medical attention is necessary if symptoms like difficulty breathing or severe abdominal pain occur.
To learn more about side effects, you can read the full medical information sheet for Mounjaro®.

troubleshootMounjaro® facts

  • Treatment type
    GLP-1 + GIP injectable pen
  • Weight loss in 9 months
    Average 20.9% body weight
  • Weight loss in 20 months
    Average 25.3% of body weight
  • Available strengths
    2.5mg – 15mg
  • Active ingredient

How it works

  1. Step 1 illustration

    1. Answer quick questions

    No GP or pharmacy visits, just a quick online consultation.

  2. Step 2 illustration

    2. Choose a GLP-1 treatment

    Select from our recommended UK-licensed weight loss injectables.

  3. Step 3 illustration

    3. Get it delivered direct

    Your treatment arrives in discreet packaging, direct to your door.

Mounjaro® FAQs

Get started now

Backed by our experienced UK-based medical team

Dr Clare Morrison picture

Dr Clare Morrison


GMC: 3441561

Rukhsana Deshmukh picture

Rukhsana Deshmukh

Superintendent Pharmacist

GPhC: 2070765

Avnish Patel picture

Avnish Patel

Pharmacist | MPharm, PhD

GPhC: 2079950

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Authored by Dr Clare Morrison. Last reviewed 01 February 2024 by Liyya Patel and Siobhan Titre.