Everything you need to know about Mounjaro 5mg
If you're looking for support with weight loss and have heard about weekly injection treatments, you may have come across Mounjaro 5mg—a weekly injection gaining attention for supporting weight loss in people living with obesity or type 2 diabetes.
This comprehensive guide explains how Mounjaro 5mg works, what the typical treatment path looks like, common side effects, pricing information, and what to expect throughout your treatment journey.
What is Mounjaro 5mg?
Mounjaro (tirzepatide) is a prescription weight loss injection developed for adults with obesity, or those who are overweight with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea.
It's a type of medicine called a GLP-1 receptor agonist, specifically a dual GIP and GLP-1 receptor agonist, prescribed as a weekly injection to support weight loss.
The 5mg dose is part of a titration schedule, usually prescribed after an initial 2.5mg dose to help your body adjust gradually and minimise side effects.
This is typically the second dose in your treatment journey, introduced after at least four weeks on the 2.5mg starting dose, once your body has had time to adjust to treatment. Patients typically move through doses every four weeks, with 5mg being one of the maintenance doses for long-term treatment.
How does Mounjaro 5mg work?
Mounjaro belongs to a class of medicines called dual GIP and GLP-1 receptor agonists, which means it mimics two natural hormones in your body that help manage appetite and blood sugar levels.
Although it's a higher dose than the starter 2.5mg, Mounjaro 5mg works in the same way by mimicking natural hormones that help regulate your appetite and blood sugar.
Here's how it helps with weight loss:
- Reduces appetite by slowing digestion and increasing feelings of fullness
- Improves insulin sensitivity, making it easier for your body to manage glucose
- Decreases food cravings, especially when combined with a calorie-controlled diet
- Makes it easier to reduce calorie intake and stick to long-term lifestyle changes
Clinical trials show that people taking tirzepatide could lose around 25% of their starting weight[1] after 88 weeks of treatment.
Mounjaro 5mg dosing schedule
Mounjaro pens are available in six different strengths, so it's important to find the right dose and schedule for your needs. The typical dosing progression follows this pattern:
- Weeks 1–4: 2.5mg once weekly
- Weeks 5–8: 5mg once weekly (if tolerated)
- Following months: May increase to higher doses based on individual response
It's important to follow your prescriber's guidance and never skip or alter your dosage without a consultation. Your prescriber will provide clear guidance on when and how to make this change, typically around four weeks after starting treatment, provided you're tolerating it well and not experiencing any unmanageable side effects.
Changing to the 5mg dose
Once you've completed your starter dose of Mounjaro (2.5mg), you can move on to the 5mg dose as part of your usual weekly schedule.
You'll continue taking it once a week, on the same day and at the same time as before. There's no special process in changing doses—just start using the 5mg pen when your next dose is due.
If you are experiencing side effects, or if you're happy with the weight you're losing on the 2.5mg dose, you may be advised to stay on the starter dose a little longer before increasing to 5mg.
What to expect when changing dose
When you increase your dose to Mounjaro 5mg, you may notice a few changes, such as a more reduced appetite or an increase in side effects. This is completely normal and common when moving to a higher dose, as your body adjusts to the change in medication.
Because 5mg is a stronger dose, you might find that your appetite decreases further, or that you feel the effects of the medication a little more. However, any side effects should subside once your body adjusts to the new dose.
Mounjaro 5mg side effects
Like all medicines, Mounjaro may cause side effects, but most people find these are mild and improve as their body gets used to the treatment. The side effects of Mounjaro 5mg are similar to those experienced with other doses, as it's the same medicine, just in a higher amount.
Common side effects may include:
- Nausea (feeling sick)
- Diarrhoea or constipation
- Reduced appetite
- Indigestion or bloating
- Vomiting
- Headache
- Fatigue
- Low blood sugar (especially if taken with certain diabetes medications)
When increasing your dose to 5mg, you may notice side effects reappearing or becoming more noticeable. This is normal, as your body adjusts to the higher dose. It's one of the key reasons why Mounjaro is prescribed in gradually increasing steps, to help minimise side effects and give your system time to adapt.
Rare but serious side effects:
- Pancreatitis (inflammation of the pancreas)
- Gallbladder problems
- Kidney issues
- Low blood sugar (particularly in people taking insulin)
- Allergic reactions
If you experience intense abdominal pain, signs of an allergic reaction, or persistent vomiting, seek medical advice immediately. For a full list of side effects, read the official patient information leaflet or speak to your prescriber.
Mounjaro 5mg pricing in the UK
When it comes to Mounjaro 5mg prices, costs can vary depending on whether you're buying privately or accessing the medication through a weight management service. The cost typically ranges from £129 to £250 for a four-week supply in the UK.
It isn't currently accessible through all NHS services, as it's being introduced in phases.
Starting in March 2025, certain patients became eligible to receive Mounjaro via specialist NHS weight management services. These specialised clinics are designed for individuals with severe obesity requiring intensive support, and patients can only access them with a referral from their GP.
In June 2025[2], select patients may be able to obtain it directly through their GP practice. However, this option is limited to those who meet strict eligibility requirements and are classified as high-risk patients.
Who is Mounjaro 5mg suitable for?
Mounjaro could be an option if you:
- Have a BMI of 30 or higher (or 27+ with weight-related health conditions)
- Have struggled with weight loss through diet and exercise alone
- Are not pregnant or breastfeeding
- Are willing to follow a calorie-controlled diet and lifestyle plan
- Have successfully completed the initial 2.5mg dose phase
Eligibility must always be assessed through a medical consultation with a qualified healthcare provider.
Staying on the 5mg dose
You can stay on your current dose for longer if you're happy with the weight you're losing, or if you're experiencing side effects that are difficult to manage. In fact, some patients have seen strong results by remaining on the 5mg dose for an extended period.
To get the most out of Mounjaro, healthcare providers usually recommend following a dosing schedule where you slowly increase your dose each month, a process known as titration. This helps your body adjust to treatment gradually and better supports long-term success.
Over time, you'll reach what's known as your maintenance dose—the dose that delivers the best results for you that you'll remain on for most of your treatment. For some people, this may be 5mg, while for others, it may be a higher dose, up to 15mg per week.
Why choose a trusted provider?
While prices of Mounjaro 5mg may differ between online providers, it's important to make sure you're choosing a trusted and regulated service, like us here at Chemist4U. This ensures you'll get:
- Authentic medication: Mounjaro sourced directly from the manufacturer
- Professional oversight: Every prescription is reviewed by a qualified prescriber
- Comprehensive support: Ongoing access to medical advice and treatment plans
- Safety assurance: Protection against counterfeit products and improper use
Always check that providers are regulated and that treatment is dispensed from registered pharmacies. Be cautious of unusually low prices, which can be a sign of counterfeit medication or a lack of proper medical oversight.
Mounjaro 5mg is a promising option for people struggling with weight loss. As a mid-point in the dosing schedule, it plays a key role in building tolerance while delivering appetite control and metabolic support. When combined with a healthy diet and exercise plan, it can help achieve impressive weight loss results.
Your healthcare provider will work with you to determine the right dose and treatment plan based on your individual response, weight loss goals, and any side effects you may experience.
Remember that results can vary, and everyone loses weight at their own pace. If you're unsure about any aspect of your treatment, or if side effects are difficult to manage, always speak to your pharmacist for personalised advice and support.
