Can You Continue to Lose Weight on 2.5mg Mounjaro? (October 2026)

01 · The core answer

Will you keep losing weight on 2.5mg Mounjaro?

You may well keep losing weight on 2.5mg, but you should not expect it to carry you all the way to your goal. The first weeks on 2.5mg are an adjustment phase and losses are usually modest; most measurable progress builds from 5mg onward, month by month.¹ That is why a prescriber plans a step-up rather than leaving you on the starting strength indefinitely.

Individual response is genuinely wide. Some people notice a quieter appetite and a drop on the scales within days of the first injection. Others see almost nothing for several weeks and then respond once the dose rises. Neither pattern tells you how well the treatment will work for you over the longer term.

02 · What to decide

The two decisions you are really facing

Most people asking this question are in one of two positions. Either you are just starting and wondering whether slow early progress means the medicine is not working, or you have been on 2.5mg for a while and the scale has stopped moving. The right response differs for each.

If you are early in treatment, the main task is patience and consistency. Mild nausea, altered appetite and tiredness in the first days after each injection are the commonest early effects and usually settle.¹ Focus on protein, portion sizes and activity, and keep a simple record of your weight trend rather than reacting to each weigh-in. Our page on whether you can lose weight on the starting dose goes deeper on the early weeks.

If you have stalled, the question is whether you have simply reached the limit of what the starting strength offers. Your prescriber can discuss whether a dose step-up is appropriate if you are not yet at maximum.¹ A plateau is not a reason to double doses or add unlicensed products.

03 · Judging progress

How to judge whether 2.5mg is working

If you want to start treatment, you can see the Mounjaro pen and start a free consultation. Every order is reviewed by a GPhC-registered prescriber, and ongoing monthly reviews cover dose-titration and follow-up. For wider support, see our weight loss clinic page.

Treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them, and individual results vary.² The honest summary is that 2.5mg is a sensible, well-tolerated place to begin, a reasonable place to see early effects, and rarely the dose where most of your loss happens.

You may also want to read whether staying on the starting strength is realistic, and what to do if you are not losing weight at all.

04 · What 2.5mg is for

What the 2.5mg strength is designed to do

The 2.5mg pen is the lowest of six Mounjaro strengths, and its job is to introduce your body to the medicine. Mounjaro is the brand name for tirzepatide, a once-weekly injectable prescription medicine made by Eli Lilly. It comes as a pre-filled multi-dose pen (KwikPen) in six strengths: 2.5mg, 5mg, 7.5mg, 10mg, 12.5mg and 15mg.¹ Starting at the bottom of that range gives your digestive system time to adapt before the dose rises.

That adjustment role matters for how you should think about weight loss at this strength. The first weeks on 2.5mg are an adjustment phase and losses are usually modest.¹ This does not mean nothing is happening. The medicine is active from the first injection, and plenty of people feel a change in appetite. It means the strength is chosen for tolerability first and for results second.

To understand why a starting dose can still help, it is worth looking at how tirzepatide works. It is the first treatment of its kind to activate two natural gut-hormone receptors at once: GIP and GLP-1. Together these help regulate appetite, slow how quickly the stomach empties, and improve the way the body responds to insulin.¹ In practice, most people feel fuller sooner and less hungry between meals, which supports a reduced-calorie diet.

Because the effect on appetite is real even at a low strength, it is entirely reasonable for the scale to move on 2.5mg. The effect is typically smaller than at higher strengths. If you notice hunger returning strongly before your next injection, that is useful information for your prescriber rather than a reason to change anything yourself.

It also helps to know what 2.5mg is not. It is not a way to "test" whether the medicine suits you in the long term, and it is not designed as a place to remain for months while waiting for results to arrive.

Tolerability is the other half of the story. Gentle introduction means the commonest early effects, such as mild nausea, altered appetite and tiredness in the first days after each injection, are more likely to be manageable and to settle.¹ If side effects are heavier than you expected, tell your prescriber. The patient information leaflet lists what to expect and when to seek advice.¹³

Finally, remember that Mounjaro is a prescription-only medicine, supplied only after an online consultation reviewed by a GPhC-registered prescriber. It is used alongside a reduced-calorie diet and increased physical activity, and individual results vary. The pen you start with is chosen to fit that clinical process, not to maximise early scale movement.

05 · The first weeks

What the first weeks on 2.5mg usually look like

The first weeks vary enormously, and most variations are normal. The 2.5mg starting weeks are about adjustment, and experiences differ widely: some people notice appetite change and early loss in week one, others feel little until a higher dose — both are normal.¹ If you are comparing yourself with a friend or someone online, bear in mind that you are comparing two different bodies responding to the same signal.

Early loss includes water weight, so the trend over weeks matters more than any single weigh-in.¹ A sharp drop in the first days is often partly fluid and gut contents, especially if you are eating less. It does not predict that the same pace will continue, and it is not a sign that you are doing better than someone with a quieter start. Equally, a flat first few weeks is not a sign of failure.

Weigh yourself at a consistent time, under similar conditions, and look at the direction of travel across several weeks. Many people find that a weekly average is far more reassuring than daily readings, which bounce around with hydration, salt, digestion and hormones. A simple log, whether on paper or in a free companion app such as GLPTrackr, makes the trend visible without obsessing over each number.

Appetite is often the earliest signal. You may find you are satisfied with smaller portions, that snacking between meals falls away, or that thoughts about food become quieter. Those changes can precede any visible change on the scales. They are worth noticing because they are the behavioural foundation on which later loss is built, and they are a good sign that the medicine is acting even if your weight has barely shifted.

Side effects tend to cluster around injection day. Mild nausea, altered appetite and tiredness in the first days after each injection are the commonest early effects and usually settle.¹ Eating smaller meals, avoiding very rich or greasy food, and staying hydrated are sensible habits. If symptoms are severe, persistent or alarming, contact your prescriber, and consider reporting suspected side effects through the Yellow Card scheme.¹⁹ Severe, persistent stomach pain, swelling of the face or throat, or difficulty breathing need medical help straight away.

It is also common to feel uncertain about whether the medicine is "doing enough". That worry is understandable when the scale is not dramatic. The reassuring point is that the dose you respond to may still be ahead of you, and the plan is designed so that your prescriber can step up when you are ready. Our page on whether people lose weight on the starting dose explores how varied this experience is.

Finally, protect the basics. Eat enough protein, keep moving in a way you enjoy, sleep properly and keep alcohol modest. The medicine reduces appetite; it does not replace the habits that make the loss sustainable. Treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them.²

06 · Realistic pace

Realistic pace: think in months, not days

Weight loss on Mounjaro is gradual by design, so the right unit for measuring progress is months. Trials measured results at 72 weeks, which is a long time frame compared with how people often judge a diet.¹ Think in months, not days, and judge progress by trend, not individual weigh-ins.

By the three-month mark most people are still on the lower rungs of the dose ladder, so trial-average losses at this stage are modest compared with the headline figures. In SURMOUNT-1, average weight loss built month by month, with the full 15–21% averages measured at 72 weeks, not 12.² A sensible three-month expectation on a standard titration is mid single digits as a percentage of body weight, with wide individual variation.²

That framing is important for anyone who is on 2.5mg and wondering whether they are behind. Staying on the lowest strength for a period is part of the normal path, and a modest total at this stage is expected rather than disappointing. Slower early progress does not predict failure — the dose you respond to may still be ahead of you.²

Your prescriber also reviews response formally. Treatment response is reviewed by your prescriber: if you have lost less than 5% of your starting weight after 6 months on the highest dose you can tolerate, your prescriber will discuss whether continuing or stopping is right for you.¹ The checkpoint is measured on the highest tolerated dose, not on the starting strength. A slow start on 2.5mg is not judged by the same standard.

Trial averages are not forecasts for you personally, and any individual may land above or below them. Think of the SURMOUNT-1 figures as showing the shape of the curve over a long period, not as a schedule to be met at each appointment.

A few practical habits keep expectations realistic. Decide in advance how you will measure progress, for example a weekly average weight and a monthly waist measurement. Resist reading meaning into any single reading. Share the trend, not the daily numbers, with your prescriber at reviews. And remember that the medicine's job is to make eating less feel easier, so your own consistency still sets the pace.

NICE recommends tirzepatide for adults who meet its criteria, and its guidance sits within a wider approach that includes diet and physical activity.⁴ That framing is the same one your prescriber uses: medicine plus lifestyle, reviewed regularly, adjusted over months. If you would like a broader look at how much to expect overall, see our page on whether you will definitely lose weight on Mounjaro, which is honest about the range of outcomes.

07 · Why higher doses help

Are higher doses of Mounjaro more effective?

In the main trial, higher strengths were associated with larger average losses. In SURMOUNT-1, a trial of 2,539 adults, people taking tirzepatide alongside diet and exercise lost on average 15% of their body weight on 5mg, 19.5% on 10mg and 20.9% on 15mg over 72 weeks, compared with 3.1% with lifestyle changes alone.² These are trial averages, and individual results vary.

This is why most measurable progress is described as building from 5mg onward.¹ It also explains why a prescriber will not usually leave you on 2.5mg for the long term if you are tolerating treatment and have more weight to lose. The dose ladder exists because the benefit generally rises with dose, while tolerability is built up step by step.

The trial also reported how many participants reached particular thresholds. At 72 weeks, 85% of participants on 5mg, 89% on 10mg and 91% on 15mg had lost at least 5% of their body weight. Half of participants on 10mg and 57% on 15mg lost at least 20% of their body weight.² Those figures describe groups over a long period, and they do not tell you what you will achieve at any stage.

A worked example makes the headline percentage more tangible. For someone starting at 100 kg, 20.9% is about 21 kg. That is the straight arithmetic of the trial average at the highest strength over 72 weeks, not a prediction for any individual and not something that happens in the first months on 2.5mg.

It is also worth being clear about what "more effective" does and does not mean. A higher dose is not automatically better for everybody. Some people respond well and tolerate a middle strength, and their prescriber may agree that they stay there. Others need to go higher to keep progressing. The right maintenance strength is the one that gives you worthwhile results with side effects you can live with, decided with your prescriber rather than by chasing the top of the ladder.

If you want to understand the specific differences between the first two strengths, our page asking whether 2.5mg is enough to lose weight compares them directly. In short, 2.5mg is about introduction, 5mg is where more people begin to see steadier progress, and later steps are tailored to how you respond.

08 · Plateaus and stalls

When the scale stops moving

A pause in loss is common and rarely a sign that treatment has failed. Weight loss on Mounjaro is not linear — plateaus of a few weeks are normal and expected as the body adapts to a lower weight.¹ If you are on 2.5mg, a stall may also reflect that you have gone as far as the starting strength allows.

The first question is how long the pause has lasted. A few weeks of flat readings, particularly after an early drop that included water weight, is within normal variation. Look at the weekly average rather than daily numbers, and compare against a month ago rather than last week. If the trend is flat over a longer stretch, it is time to act, but within the licence.

Within the licence, the responses are: review food intake honestly (portions drift back up), protect protein and activity, check the basics (sleep, alcohol), and discuss with your prescriber whether a dose step-up is appropriate if you are not yet at maximum.¹ Each part of that list matters. Portion drift is the commonest hidden factor, because when appetite is quieter it is easy to let calorie-dense foods creep back in without noticing.

Protein and activity protect your muscle as weight falls, which supports your metabolism and how you feel. Sleep and alcohol affect appetite signals and judgement around food. None of these are glamorous, but they are the levers you control, and they work alongside the medicine rather than competing with it.

The prescriber conversation is the other lever. If you are on 2.5mg and have stalled, a step-up may be appropriate when you are tolerating treatment well. If you are already at a higher strength, the discussion may be about whether to hold, adjust or review the plan. A plateau is not a reason to double doses or add unlicensed products.¹ Taking extra injections, shortening intervals or mixing in other products brings risks that the licensed plan is designed to avoid.

If you are not losing at all, it can help to check the practical side. Are you injecting on the same day each week as instructed? Are you following the pen's instructions? Has anything changed in your medicines, illness or routine? Our page on not losing weight on the starting strength walks through these checks in more detail.

Finally, treat a plateau as information, not a verdict. Many people who stall on a lower strength resume steady progress after a considered step-up and some tightening of habits. Others find that holding steady for a period is exactly what they need while they adapt. Either way, your prescriber can help you choose, and you do not need to decide alone.

09 · Beyond the scales

Progress that does not show on the scales

The number on the scales is only part of what Mounjaro is for. In trials, weight loss on tirzepatide came with average improvements in waist size, blood pressure, cholesterol and blood-sugar measures, and most participants with prediabetes returned to normal blood-sugar levels.² These are trial-average secondary outcomes, not promises, but they are why prescribers talk about weight management as health management rather than appearance.

This matters when you are on 2.5mg and the scale is moving slowly. Other signals may already be shifting. You may notice clothes fitting differently, a smaller waist measurement, more energy, or a calmer relationship with food. These are legitimate markers of progress, and they are often visible before the scale tells a convincing story.

A balanced tracking routine therefore includes more than weight. Consider a monthly waist measurement taken at the same point, a note on appetite and how often you think about food, and how your energy and sleep are doing. If you have blood pressure or blood sugar monitoring as part of your care, share those readings at reviews. They help your prescriber see the whole picture rather than a single metric.

It is worth being careful about expectations here too. Trial-average improvements describe groups, and your own measurements may differ. Do not treat the absence of change in one measure as failure, and do not assume that every measure will improve. What the evidence supports is that, for many people, sustained loss goes hand in hand with healthier readings over time, which is the reason to persevere through the slower early period.

Treatment response is reviewed by your prescriber, and the review covers more than a weight figure. Tolerability, appetite, your goals and your wider health all feed into decisions about whether to continue, adjust or stop.¹ That is part of the ongoing monthly reviews, dose-titration and follow-up assessments carried out by the prescribing team.

Mental and emotional signals count as well. Many people describe the early weeks as a change in how loud food feels. It is not a clinical measure, but it is a reasonable thing to mention to your prescriber, particularly if it changes over the course of the week. If you notice any new or worrying symptoms, discuss them with your prescriber and report suspected side effects through the Yellow Card scheme.¹⁹

The takeaway for the 2.5mg stage is simple: do not let the scale alone decide whether the treatment is working. Use the trend, the tape measure, your appetite and how you feel, and bring them to your review.

10 · Cost and NHS access

Cost, NHS access and planning your titration

Because most measurable progress builds from 5mg onward, it helps to plan the cost of the whole journey rather than the first pen alone. Your first 2.5mg pen costs £129.99 with code FIRST40 (standard price £169.99), and the Mounjaro pen at 5mg is £218.99 at standard price. Every later order is £25 off the standard price (code DOSE25), and a new customer's first order is £40 less at any dose.

If you step up after 4 weeks on each dose, your first four pens (2.5mg to 10mg) cost £959.96 at standard prices, before discounts. A first year costs £2,711.88 if you settle at 5mg, up to £3,599.88 at 15mg, again before discounts. If you settle at another strength, the monthly price is £279.99 at 7.5mg, £290.99 at 10mg and £319.99 at 12.5mg. Prices were checked 11 October 2026, and the price shown is the price paid.

On the NHS side, the picture is honest but phased. Mounjaro is available on the NHS, but access is being phased in over several years. NICE recommends it for adults with a BMI of at least 35 plus at least one weight-related condition, and the NHS primary-care rollout began in June 2025 with the highest-need groups first (initially BMI 40+ with four or more qualifying conditions).⁴⁶ Full rollout is expected to take years, which is why many people who meet the licensed criteria choose regulated private treatment rather than waiting.

If you go private, the service we describe is straightforward. You complete a free online consultation and a GPhC-registered prescriber reviews it. If the prescriber decides the treatment is not suitable, the order is refunded automatically in full. Orders are dispensed by our registered pharmacy (GPhC 9012878), with same-day dispatch when ordered by 3pm and free next-day tracked delivery in temperature-controlled packaging. Mounjaro is supplied through official LillyDirect supply, and all six doses are in stock.

Aftercare is part of the offer: ongoing monthly reviews, dose-titration and follow-up assessments by the prescribing team, and side-effect support. Repeat orders re-check suitability, with no auto-shipping, and there are no subscriptions. Klarna and pay-monthly options are available if you prefer to spread the cost.

Always confirm current prices on the product page before ordering. Mounjaro is a prescription-only medicine, used alongside a reduced-calorie diet and increased physical activity, and individual results vary.

11 · Stopping and safety

Safety, side effects and what happens if you stop

Staying safe at the starting strength is mostly about knowing what is normal and when to ask for help. Mild nausea, altered appetite and tiredness in the first days after each injection are the commonest early effects and usually settle.¹ The patient information leaflet lists the full range of possible effects and the situations in which you should seek medical advice, and it is worth reading it before your first injection.¹³

If a symptom is new, severe or worrying, contact your prescriber. If you suspect a side effect, you can report it through the MHRA Yellow Card scheme.¹⁹ A symptom that is not listed in the patient leaflet is not a listed side effect, but tell your prescriber about any new or lasting symptom.

People sometimes ask what happens if they decide 2.5mg is not for them and stop. Tirzepatide has a half-life of about five days, so after a final dose it takes roughly four to five weeks to clear the system. There is no way to speed this up, and nothing needs doing while it clears.¹ Mounjaro manages weight; it does not cure the biology behind it. In SURMOUNT-4, people who stopped tirzepatide after 36 weeks regained on average 14% of body weight over the following year, while those who continued treatment lost a further 5.5% on average. Stopping should always be planned with your prescriber, with diet and activity habits ready to carry the load. That also means that the effects of a dose are not switched off instantly if you skip an injection, and it is one reason not to improvise with timing.

Do not try to extend the starting strength by dividing doses, adding extra injections or changing the schedule yourself. Those approaches are outside the licence and the evidence base, and they carry risks that your prescriber cannot manage if they do not know about them. If you are unhappy with the pace of progress, the right step is to tell your prescriber and discuss a licensed adjustment.

Medicine interactions deserve a mention too. If you take other medicines, particularly insulin or sulfonylureas for diabetes, tell your prescriber, because doses may need reducing to avoid low blood sugar. Likewise, Mounjaro slows stomach emptying, which can reduce how well oral contraceptive pills are absorbed.⁷ The SmPC advises switching to a non-oral method, or adding a barrier method (such as condoms), for 4 weeks after starting Mounjaro and for 4 weeks after each dose increase.¹

Finally, beware of sellers offering to supply without a consultation or prescription. Genuine Mounjaro is supplied only after a consultation reviewed by a GPhC-registered prescriber, and you can check any pharmacy on the GPhC register. Counterfeit medicine alerts are published by the MHRA, and buying from a regulated pharmacy is the simplest protection.⁷¹²

The overall message for the starting strength is reassuring. It is chosen to be gentle, most side effects are mild and settle, and your prescriber is there to adjust the plan as you go.

12 · Serious side effects

Serious side effects: when to get help straight away

Serious side effects are uncommon but need urgent attention. Seek immediate medical help for: severe, persistent stomach pain that may spread to your back, with or without vomiting (possible pancreatitis); pain in the upper right abdomen, fever or yellowing of skin/eyes (possible gallbladder problems); or signs of a severe allergic reaction such as swelling of the face or throat and difficulty breathing. If you take insulin or a sulfonylurea alongside Mounjaro, watch for low blood sugar (shakiness, sweating, confusion) — your prescriber may need to adjust those medicines.¹