Mounjaro 2.5mg Injection

Mounjaro 2.5mg (tirzepatide) is the standard starting dose used for the first 4 weeks of treatment¹. Its purpose is to:

• Help your body adapt to the medication.
• Reduce the chance of side effects such as nausea or stomach upset.
• Prepare you for dose increases to 5mg and beyond, where most people begin to see noticeable weight loss.

• Typical duration – 4 weeks
• Injection – Once weekly
• Common side effects – Mild nausea, bloating, fatigue
• Expected weight loss – Minimal, the main weight loss starts at 5mg and above²
• Next step – 5mg (after review with a clinician)

You can start safely from home – no GP visit required. Here’s how it works:

1. Complete a short online assessment (about 5-10 minutes).
2. A UK-registered clinician reviews your answers.
3. If suitable, Mounjaro is prescribed.
4. Your 2.5mg pen is delivered discreetly to your door.

At Medicspot, your clinician will check your NHS Summary Care record as part of their prescribing decision. This ensures every prescription is clinically appropriate and tailored to your needs, in line with MHRA guidance³.

A Mounjaro 2.5mg pen costs £149 for the first 4 weeks.

Repeat Mounjaro 2.5mg pens cost £199.

All prices include a clinical review, dispensing, next-day delivery, ongoing coaching, and clinical support.

Medicspot also includes 12 months of free aftercare, giving you continued coaching support to help you maintain your results and feel confident as you transition off treatment.

Mounjaro is injected once a week under the skin, usually into an area with the most fatty tissue such as your stomach, thigh or upper arm.

• Pick the same day each week (e.g. Friday) and a time you can easily remember.
• Rotate injection sites to reduce irritation.
• You can take Mounjaro with or without food.

✅ Keep Mounjaro refrigerated (2-8°C)⁴

✅ Do not freeze

✅ If needed, you may store at room temperature (up to 30°C) for up to 30 days

❌ Do not use after the expiry date

❌ Avoid direct sunlight or heat

❌Never use a needle more than once

• Week 1: You may not feel much appetite suppression yet.
• Weeks 2-3: Mild nausea, bloating, or tiredness may appear as your body adjusts.
• Week 4: Your clinician will usually review your progress and discuss moving up to 5mg. This is when most people start seeing meaningful weight loss.

Most people tolerate the starting dose well. Mild effects may include:

• Nausea or feeling full quickly
• Bloating or constipation
• Fatigue
• Headache

These typically settle within a week or two as your body adapts⁵. Eat smaller meals, limit high-fat foods, and sip water throughout the day. If symptoms persist or feel severe, contact your clinical team for personalised advice.

After 4 weeks on 2.5mg, your clinician will review your progress and confirm if you’re ready to move up to 5mg. This is the first therapeutic dose for weight loss.

Some people may stay at 2.5mg longer if side effects take a bit more time to settle.

Although 2.5mg is mainly a starting dose, your clinician might recommend stepping back down temporarily if needed.

If side effects occur at higher doses

Reducing to 2.5mg for a short time can help your body reset and tolerate the medication better. Once you feel well again, you and your clinician can plan a slower titration back up.

When tapering off Mounjaro

If you’ve reached your goal weight and want to stop safely, 2.5mg can be used as a transition dose to reduce the chance of your appetite rebounding while your natural hormone levels readjust. This should always be done under clinical supervision.

Your first few weeks on Mounjaro 2.5mg are about getting comfortable, not rushing results.

This early phase is designed to help your body adjust gently, laying the foundation for safe and sustainable progress as you move to higher doses. Be patient with yourself, listen to your body, and focus on consistency rather than speed.

If you ever feel unsure or need extra support, our clinical and coaching teams are here to help you every step of the way.

¹ National Institute for Health and Care Excellence (NICE) Guideline. “Overweight and obesity: management (NG246)”. Last accessed November 2025. [https://www.nice.org.uk/guidance/ng246/]

² Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide once weekly for the treatment of obesity. The New England Journal of Medicine. Last accessed November 2025. [https://www.nejm.org/doi/full/10.1056/NEJMoa2206038]

³ MHRA news release. “MHRA authorises diabetes drug Mounjaro (tirzepatide) for weight management and weight loss.” Last accessed November 2025. [https://www.gov.uk/government/news/mhra-authorises-diabetes-drug-mounjaro-tirzepatide-for-weight-management-and-weight-loss]

⁴ Eli Lilly. Mounjaro® Patient Booklet (UK). Last accessed November 2025. [https://uk.lilly.com/metabolic/assets/pdf/mounjaro-patient-booklet.pdf]

⁵ Coventry and Warwickshire Formulary. “Medicines Safety Spotlight – Tirzepatide (Mounjaro®)” Last accessed November 2025.
[https://www.covwarkformulary.nhs.uk/docs/chapter06/RD054-Medicines%20Safety%20Spotlight%20tirzepatide.pdf]

Eli Lilly and Company Ltd. “Mounjaro® KwikPen 2.5 mg solution for injection in pre-filled pen – Summary of Product Characteristics (SmPC).” Electronic Medicines Compendium (eMC). Last accessed November 2025. [https://www.medicines.org.uk/emc/product/15481/smpc]

This article is for general information only and should not be used for the diagnosis or treatment of medical conditions. Medic Spot Limited has used all reasonable care in compiling the information but makes no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. In the event of an emergency, please call 999 for immediate assistance.

There is no guarantee of a specific weight loss medication being prescribed. Clinicians will review your online questionnaire and will recommend the most appropriate weight loss treatments for you based on your answers. In some cases the clinicians may contact you for additional information. See our Terms of Service for more information.