Weekly injection, tirzepatide
Mounjaro weight loss injection
Mounjaro is a weekly tirzepatide injection. One KwikPen holds four doses, a month of treatment. The medicine works on two appetite hormones, so you feel full sooner and stay full longer.
Prices to be confirmed
Starter dose, weeks 1 to 4
Explore MounjaroThe planned service requires a clinical assessment before any treatment can be supplied. The secure assessment is not connected in this preview. Read how assessment works or prepare a discussion checklist. Provider details, prices and delivery arrangements must be confirmed before launch.
- UK prescriber review
- Planned dispensing: Pharmacy2U
- Delivery arrangements to be confirmed
In short: Mounjaro (tirzepatide) is a once-weekly injection in six doses from 2.5 mg to 15 mg. Average weight loss was 20.9% at 72 weeks on 15 mg in the SURMOUNT-1 trial. Aero’s prices are not yet confirmed.
How Mounjaro works
Your gut releases GLP-1 and GIP after you eat. These hormones tell your brain you are full and slow the speed food leaves your stomach.
Tirzepatide copies both hormones and lasts a full week. Hunger drops, portions shrink, and cravings between meals fade for most people. Many describe the constant "food noise" going quiet.
The medicine supports change and does not replace your own habits. Protein at each meal, regular movement and good sleep protect your muscle and help results last. Read the protein guide and the exercise guide.
Mounjaro doses and prices
Everyone starts at 2.5 mg. Each step lasts at least 4 weeks. You move up only when you and your prescriber agree.
| Dose | Price a month | Stage | Price per weekly dose |
|---|---|---|---|
| 2.5 mg | To be confirmed | Starter dose, weeks 1 to 4 | To be confirmed |
| 5 mg | To be confirmed | First maintenance dose | To be confirmed |
| 7.5 mg | To be confirmed | Optional step | To be confirmed |
| 10 mg | To be confirmed | Maintenance dose | To be confirmed |
| 12.5 mg | To be confirmed | Optional step | To be confirmed |
| 15 mg | To be confirmed | Highest dose | To be confirmed |
Missed a dose? Take your dose within 4 days (96 hours). After 96 hours, skip the dose and continue on your usual day. See the missed dose guide and the full Mounjaro dose schedule.
What the trials found
SURMOUNT-1 tested tirzepatide 15 mg in 2,539 adults for 72 weeks, alongside diet and activity support.
20.9%
average weight loss, counting every participant. The placebo group averaged 3.1%.
Other trials
- SURMOUNT-4 (withdrawal). After a 36-week tirzepatide lead-in with 20.9% mean weight loss, 670 adults were randomised. Over the next 52 weeks weight changed by -5.5% with continued tirzepatide and +14.0% with placebo. Total loss from week 0 to 88 was 25.3% versus 9.9%. 89.5% versus 16.6% kept at least 80% of the lead-in loss.
- SURMOUNT-5 (head to head). In 751 adults with obesity without type 2 diabetes, mean weight change at 72 weeks was -20.2% with tirzepatide (10 or 15 mg) and -13.7% with semaglutide (1.7 or 2.4 mg). Waist change was -18.4 cm versus -13.0 cm. Open-label trial.
- SURMOUNT-OSA. In adults with moderate to severe obstructive sleep apnoea and obesity, AHI fell by 25.3 events per hour with tirzepatide versus 5.3 with placebo in people not using PAP, and by 29.3 versus 5.5 in people using PAP, at 52 weeks.
Side effect rates in trials
| Effect | Rate | Dose |
|---|---|---|
| Nausea | 28% | 15 mg |
| Diarrhoea | 22.5% | 15 mg |
| Vomiting | 13% | 15 mg |
| Constipation | 11% | 15 mg |
| Abdominal pain | 10% | 15 mg |
| Dyspepsia | 10% | 15 mg |
| Injection site reactions | 8% | 15 mg |
| Fatigue | 7% | 15 mg |
Main trial: Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide Once Weekly for the Treatment of Obesity. N Engl J Med 2022, 387(3):205-216. Individual results vary, and no result is promised.
Questions about support for Mounjaro
Aero’s treatment prices and service inclusions will be confirmed before booking opens. Ask which prescribing, dispensing, delivery and follow-up costs are included in your quote.
- Before treatment begins, the prescribing clinician’s identity and professional registration must be clear. Aero’s named prescriber details will be published before booking opens.
- Agree a follow-up schedule with your prescriber, including how you report progress and side effects and who decides whether a dose should change.
Ask how to contact your clinical team
Questions about side effects, injecting or travel go to the pharmacy team who dispense your medicine. Clinical support hours and response times will be confirmed before the service launches.
What support includesSide effect help when you need help
You get practical steps for nausea, constipation and reflux, plus the warning signs needing urgent care.
Side effects and problemsFood, movement and sleep guidance
Nine guides cover protein, hydration, exercise and sleep, so you keep muscle while you lose weight.
Read the guides- Ask how maintenance care will be reviewed and priced. Aero’s longer-term service arrangements will be confirmed before booking opens.
How to use your Mounjaro pen
- 1
Prepare
Wash your hands and attach a new needle for each injection. Prime Mounjaro KwikPen before every injection, following the instructions supplied with your pen. Read Lilly’s priming guidance.
- 2
Choose a site
Stomach, thigh or the back of the upper arm. Change the spot each week. See the injection guide.
- 3
Inject
Turn the dose knob until the dose shows. Press and hold, then count slowly to 5 before removing.
- 4
Dispose
Put the used needle in your sharps bin. Recap the pen and return the pen to the fridge.
Side effects and safety
Common and usually short-lived
Nausea, most often after a dose increase. Constipation or diarrhoea, reflux, tiredness and redness where you inject. Smaller meals, slower eating, less fat and plenty of water ease most of these.
Full side effects guideGet urgent help
Severe stomach pain reaching your back, pain under your right ribs with fever or yellowing skin, swelling of the face or throat, or vomiting so severe you keep no fluids down. Call 999 or go to A&E. For other concerns call 111.
Tell your prescriber about
Diabetes medicines (especially insulin or gliclazide), the contraceptive pill or HRT tablets, planned surgery with sedation, past gallbladder, kidney or pancreas problems, and any plans to become pregnant.
Report any suspected side effect through the MHRA Yellow Card scheme. Read the patient leaflet in your pack before your first dose.
Safety information for all four medicinesWhen to get urgent help
Who can start Mounjaro
Your prescriber makes the final decision after your health check.
Usually suitable
- Aged 18 to 75
- BMI of 30 or above
- BMI of 27 or above with a weight-related condition, such as high blood pressure
- Lower BMI thresholds can apply for some ethnic backgrounds
Not suitable
- Pregnant, breastfeeding or trying to conceive
- History of pancreatitis
- Personal or family history of medullary thyroid cancer or MEN2
- Type 1 diabetes, or a current eating disorder
Mounjaro key facts
The main points from the UK product information and the main trial, in one table.
| Detail | Information |
|---|---|
| Active ingredient | Tirzepatide |
| Medicine type | Dual GIP and GLP-1 receptor agonist |
| Made by | Eli Lilly |
| Form | Solution for subcutaneous injection in a pre-filled multi-dose KwikPen |
| How often | Once weekly |
| Dose range | 2.5 mg to 15 mg |
| Dose steps | 6 doses, at least 4 weeks each |
| Highest dose | 15 mg once weekly |
| Main trial | SURMOUNT-1, 2,539 people, 72 weeks |
| Average loss in the main trial | 20.9% on 15 mg, against 3.1% on placebo |
| Storage | Fridge, 2 to 8°C. Up to 30 days below 30°C once in use |
| Missed dose | Take within 4 days, then skip |
| The contraceptive pill | Can reduce the effect. Use a barrier method for 4 weeks after starting and after each dose increase |
| Stop before a planned pregnancy | At least 1 month |
| Legal status | Prescription only medicine |
| On the NHS | Limited, phased access for people who meet set criteria |
| Price at Aero Clinic | To be confirmed |
Mounjaro questions
How much does Mounjaro cost a month?
Aero’s treatment prices are not yet confirmed. Before paying, ask for the total price, pack quantity, prescribing fees, dispensing and delivery charges, and follow-up costs. Use your provider’s written quote in the cost planner.
Can I travel with my pen?
Yes. Carry the pen in hand luggage with your prescription label. An in-use pen can stay out of the fridge for up to 30 days below 30°C. Read the travel guide.
Can I drink alcohol?
Discuss alcohol with your prescriber, especially if you have side effects or diabetes. The answer depends on your health and other medicines. Our alcohol guide sets out questions to consider; it does not establish a safe personal drinking limit.
What if I stop losing weight?
A plateau is a reason to review progress with your prescriber. Discuss your dose, side effects, eating pattern and activity before changing treatment. Our plateau guide can help you prepare questions; it does not replace an individual review.
How long will I stay on treatment?
Treatment duration depends on your response, health and agreed goals. Your prescriber should explain how progress will be reviewed and when to discuss continuing, changing or stopping. Read our maintenance guide before preparing questions about longer-term care.
Does Mounjaro affect the contraceptive pill?
Mounjaro can reduce the reliability of oral contraception. Add a barrier method for four weeks after starting and after each dose increase, or discuss a non-oral method. Read the patient leaflet and seek advice about your circumstances.
Mounjaro guides
Other plans
Clinical governance
Awaiting clinical provider details
The dispensing pharmacy, GPhC registration number and Superintendent Pharmacist will be named here once confirmed. A UK prescriber reviews every order before any medicine is supplied.
Page information
- Summary
- Information about Mounjaro (tirzepatide), including weekly injection routines, dosing information, evidence, side effects and clinical assessment.
- Publisher
- Aero Clinic, operated by AERO HEALTHCARE LTD.
- Editorial update
- Clinical review
- Pending. An editorial update is not a clinical sign-off.
Cite as: Mounjaro weight loss injection, Aero Clinic (https://www.cagri.co.uk), AERO HEALTHCARE LTD. https://www.cagri.co.uk/mounjaro. Editorial update: 4 November 2026. Clinical review pending.