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Once a week
One injection a week, on the day that suits you. Four doses in every pen.
Once weekly
One small injection, on the day that suits you
Powered by tirzepatide
Around 20%
of your body weight lost, on average, in its main trial*
Mounjaro
- Lose 20% of body weight on average*
- Helps you feel full faster, longer
- Balances blood sugar, regulates insulin
From £169/ month
All doses and plansIncludes your online consultation, prescriber messaging and dose reviews.
Mounjaro® mimics two gut hormones called glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). When you eat, these hormones slow digestion and help you feel full.
Tirzepatide acts on both GLP-1 and GIP, the two gut hormones that slow digestion and tell you when you are full.
Inject under the skin of your stomach, thigh or upper arm once a week, changing the spot each time. Keep unopened pens in the fridge; the leaflet in your box says how long a pen in use can stay at room temperature.
The most common side effects of Mounjaro® are gastrointestinal issues, such as nausea, diarrhoea, vomiting, and constipation. Other common side effects include decreased appetite, indigestion, and abdominal pain. While most of these are mild to moderate and decrease over time, serious side effects can occur. These include pancreatitis, severe digestive issues, kidney problems, gallbladder problems, and a potential risk of thyroid C-cell tumours.
Tirzepatide, once a week
Get started
Two hormones, not one
Tirzepatide acts on both GLP-1 and GIP, the two gut hormones that slow digestion and tell you when you are full.
Real results
In its main trial, adults on the highest dose lost around a fifth of their body weight over 72 weeks.*
To your door, in plain packaging
Dispensed by our GPhC-registered pharmacy and sent tracked once your prescriber approves.
*SURMOUNT-1, New England Journal of Medicine, 2022. Average figures from clinical trials of Mounjaro; individual results vary. Mounjaro® is a registered trademark of Eli Lilly and Company. heySlim is not affiliated with or endorsed by Eli Lilly.
Start low,
step up gently
Starting on the lowest dose is not a delay, it is how side effects stay mild. Most people move up every four weeks. Your prescriber sets the pace, and can hold you at any step.
See what each dose costsExample dose steps, month by month
- 1 Ease in Month 1 2.5mg
- 2 Step up Month 2 5mg
- 3 Step up Month 3 7.5mg
- 4 Step up Month 4 10mg
- 5 Build Month 5 12.5mg
- 6 Maintain Month 6+ 15mg
Illustrative. Your prescriber confirms your Mounjaro dose at each review and may keep you at a step for longer.
What Mounjaro costs
One monthly price per dose, and less each month on a longer plan. Your consultation, prescriber messaging and dose reviews are included.
- 2.5mg £169/mo
- 5mg £189/mo
- 7.5mg £249/mo
- 10mg £279/mo
- 12.5mg £299/mo
- 15mg £309/mo
Included with every plan
- Your online consultation with a UK prescriber
- Messaging your care team, whenever something comes up
- A dose review every four weeks
- Pen needles and a sharps bin
- Tracked delivery in plain packaging
Check your eligibility
Your dose is confirmed by your prescriber. If treatment is not right for you, the medication cost is refunded in full.
Your prescriber,
one message away
Whatever comes up, from a queasy morning to a question at 11pm, messaging your care team is part of the plan, not an extra.
- A UK prescriber who knows your history
- Messaging included, no appointment needed
- A dose review every four weeks
- Side-effect guidance from the first week
What people say,
in their own words
“Very easy process. A short questionnaire, a quick review from the prescriber, and it arrived two days later with tracking the whole way.”
“I can’t rate heySlim highly enough. The messages I’ve had with my prescriber have been frequent and genuinely helpful. I’ve never waited long for a reply, and when I had a question about a blood test he looked over the results for me.”
“What stood out was having one prescriber who actually follows my progress. She was so reassuring in the first few weeks, answered everything quickly and adjusted the plan when I asked.”
“Approved the same day and the medication was with me the morning after. Plain box, no fuss. Couldn’t have been simpler.”
“heySlim have been brilliant from the start. Clear about what to expect, they check in every few weeks and reordering takes about a minute.”
“I liked how thorough the checks were. It made me confident that what I was buying was legitimate and that someone qualified had looked at my history. The price is fair too, not inflated because they can.”
“Fab service. Super quick approval and lovely people. I had a delivery address query and the advisor on chat sorted it in minutes.”
“No issues with delivery, ever. Communication has been fantastic, there to advise if I need it, and they keep a check on you by email. Very happy.”
How it works,
start to first delivery
Not sure this is the one?
Your prescriber recommends a treatment after your assessment. These are the others we prescribe.
Wegovy
Weekly injection · lose up to 21% body weight
- Price
- From £119/mo
- Active ingredient
- Semaglutide
- How it is taken
- Weekly injection
Wegovy Pill
A daily tablet — no injections
- Price
- From £119/mo
- Active ingredient
- Semaglutide
- How it is taken
- Daily tablet
Foundayo
Once-daily tablet — no injections
- Price
- From £119/mo
- Active ingredient
- Orforglipron
- How it is taken
- Daily tablet
Meet your
medical experts
“For too long, weight loss advice has blamed willpower. Obesity is a medical condition — and when we treat it with evidence and without judgement, lasting change follows.”
Dr. Amrit Thiara
Director of Obesity
“Successful weight management is a complex, personal journey. We're committed to an evidence-based, empathetic approach that combines advanced treatments with the support you need to make lasting changes.”
Dr. Thush Balan
Chief Medical Officer
Mounjaro questions,
answered
Written and reviewed by our clinical team. Anything else, write to support@heyslim.co.uk.
Check your eligibilityIn the UK, Mounjaro® (tirzepatide) is a prescription-only injectable medicine licensed for both managing type 2 diabetes and for weight management in adults with obesity or who are overweight with weight-related health issues. It is intended to be used in conjunction with a reduced-calorie diet and increased physical activity.
Mounjaro® has a unique dual-action mechanism. It activates two different receptors in the body: the glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors. By stimulating these receptors, it helps regulate appetite by increasing feelings of fullness and reducing hunger. It also slows down stomach emptying. This combined action helps people eat less, which contributes to significant weight loss.
The most common side effects of Mounjaro® are gastrointestinal issues, such as nausea, diarrhoea, vomiting, and constipation. Other common side effects include decreased appetite, indigestion, and abdominal pain. While most of these are mild to moderate and decrease over time, serious side effects can occur. These include pancreatitis, severe digestive issues, kidney problems, gallbladder problems, and a potential risk of thyroid C-cell tumours.
Adults (18+) with a BMI ≥30, or ≥27 with a weight-related condition (e.g., hypertension, dyslipidaemia, sleep apnoea, prediabetes/type 2 diabetes) may be considered after an online clinical assessment. Suitability depends on your medical history, medicines and treatment goals.
Tirzepatide may be unsuitable if you have a history of pancreatitis, severe gastrointestinal disease (including gastroparesis), certain thyroid problems, severe kidney impairment, or if you are pregnant or breastfeeding. Always disclose your full medical history and all medicines during your consultation.
It is a once-weekly injection. Most people start at 2.5 mg weekly for at least 4 weeks, then step up in 2.5 mg increments (e.g., 5 mg, 7.5 mg, 10 mg, 12.5 mg, up to 15 mg) at intervals of ≥4 weeks based on effect and tolerability as advised by your prescriber.
Appetite changes can appear within the first few weeks. Meaningful weight change typically becomes visible after 4–8 weeks and continues as the dose is gradually increased alongside diet and activity changes.
Results vary, but clinical trials of tirzepatide alongside lifestyle changes have shown substantial average weight loss over several months. Your outcome depends on dose, adherence, nutrition, activity levels and individual response.
They are different medicines. Wegovy®/Ozempic® contain semaglutide (GLP-1 only). Mounjaro® contains tirzepatide, which targets both GLP-1 and GIP receptors (a ‘dual-incretin’).
Yes–many patients switch under clinical supervision. Your clinician will advise washout timing, the safest starting dose on the new medicine and how to manage side effects during the transition.
Learn more about Mounjaro
Mounjaro is a prescription-only medicine, supplied subject to a clinical assessment and your prescriber's decision. Mounjaro® is a registered trademark of Eli Lilly and Company. heySlim is not affiliated with or endorsed by Eli Lilly.