Can You Take Weight Loss Injections for Just One Month? (October 2026)

01 · The short answer

Can you take weight loss injections for one month?

Yes, you can, because nothing in the licence forces a minimum course. The practical problem is the dose. Everyone starts Mounjaro on 2.5mg once a week, and that starting dose is about letting your body adjust, not about weight loss itself.¹ After at least four weeks the dose rises to 5mg, so a single month ends just as the dose reaches a level designed to do more.

Weight loss on Mounjaro is gradual by design: the first weeks on 2.5mg are an adjustment phase and losses are usually modest, with most measurable progress building from 5mg onward.¹ If you are asking about a one-month Mounjaro course, the answer is the same: possible, but not what the medicine is built to do.

Those SURMOUNT-1 figures are trial averages, and treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them.² For a closer look at what four weeks can look like, see our guide to Mounjaro before and after one month.

02 · Cost

What one month costs compared with a full plan

One month means one Mounjaro 2.5mg pen. Your first order costs £129.99 with code FIRST40, against a standard price of £169.99. If you step up after at least 4 weeks on each of 2.5mg, 5mg, 7.5mg and 10mg, your first four pens cost £959.96 at standard prices, and a new customer's first order is £40 less.

A first year costs £2,711.88 if you stay on 5mg after your 2.5mg starting pen, up to £3,599.88 if you step up through every dose to 15mg, at standard prices. Every later order is £25 off the standard price. If you only want to try it, our free consultation lets a GPhC-registered prescriber review whether it is suitable; if it is not, your order is refunded automatically in full.

Related guide: Mounjaro injection weight loss in one month.

Related guide: Can i just use mounjaro for 1 month.

03 · What month one feels like

What happens in a single month on Mounjaro

Experiences in the first month differ widely. Some people notice appetite change and early loss in week one, while others feel little until a higher dose, and both are normal.¹ Early loss includes water weight, so the trend over weeks matters more than any single weigh-in.

The commonest early effects are mild nausea, altered appetite and tiredness in the first days after each injection, and they usually settle.¹ Mounjaro works by activating two gut-hormone receptors, GIP and GLP-1, which helps regulate appetite and slows how quickly the stomach empties.¹ Most people feel fuller sooner and less hungry between meals.

Four weekly injections is one pen. Each KwikPen contains four weekly doses, injected under the skin on the same day each week.¹ Follow the pen's instructions and the patient information leaflet for technique.¹³

04 · After the last injection

What happens when you stop after one month

The medicine stays in your system for several weeks after the last dose. Tirzepatide has a half-life of about five days, so it takes roughly 4–5 weeks to clear, there is no way to speed this up, and nothing needs doing while it clears.¹ That means the effect of a single pen carries on for a while, then ends. 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.

If you want to stop, tell your prescriber so they can record it and advise on any restart.

Thinking of a gap rather than stopping for good? If you miss a dose, take it as soon as you can within 4 days (96 hours) of the scheduled time. If more than 4 days have passed, skip it and take the next one on your normal day, never two doses within 3 days of each other.¹ For longer breaks, ask your prescriber how to restart.

05 · Shortcuts to avoid

Getting Mounjaro safely

Be wary of anyone offering to supply without a consultation or prescription. Mounjaro is a prescription-only medicine and should come from a registered pharmacy, which you can check on the GPhC register.

06 · Healthy pace of loss

Is it possible to lose weight in 30 days, and what is a healthy rate?

Some weight change in 30 days is possible, but a dramatic one-month result is not what trials measured. SURMOUNT-1 measured results at 72 weeks, so think in months, not days, and judge progress by trend rather than individual weigh-ins.¹²

Plateaus of a few weeks are normal as the body adapts to a lower weight. Responses within the licence are to review food intake honestly, protect protein and activity, check sleep and alcohol, and ask your prescriber whether a dose step-up is appropriate. A plateau is not a reason to double doses or add unlicensed products.¹

Beyond the scales, trial weight loss on tirzepatide came with average improvements in waist size, blood pressure, cholesterol and blood-sugar measures. These are trial averages, not promises.²

07 · Is it right for you

Who Mounjaro is licensed for

Mounjaro is licensed for weight management in adults with a BMI of 30 or above, or a BMI between 27 and 30 with at least one weight-related condition such as high blood pressure, high cholesterol, obstructive sleep apnoea, cardiovascular disease, prediabetes or type 2 diabetes. It must be used alongside a reduced-calorie diet and increased physical activity.¹ A prescriber assesses your BMI, medical history and current medicines first.

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 primary-care rollout began in June 2025 with the highest-need groups first.⁴

08 · How ordering works

How ordering works

First, complete a free online consultation, a short health questionnaire with no charge and no obligation. Second, a GPhC-registered prescriber reviews your answers. Payment is taken when you place the order; if the prescriber decides the treatment is not suitable, the order is refunded automatically in full. Third, our registered pharmacy dispenses it, with same-day dispatch when ordered by 3pm and free next-day tracked delivery in temperature-controlled packaging. All six doses are in stock, supplied through official LillyDirect supply.

Ongoing monthly clinical reviews are included, and repeat orders re-check suitability with no auto-shipping or subscription lock-in. Other pages cover local questions, such as taking Mounjaro for one month.