How to Get the Last Shot of Mounjaro (Safely) (October 2026)

01 · The short version

What to do when you reach your last Mounjaro shot

Treat dose four exactly like doses one to three: same weekly day, a rotated injection site, and the correct number showing in the dose window.

For more on so-called extra doses, see our guides on the so-called golden shot and extra shots of Mounjaro.

What does help is planning. Your weekly schedule only stays unbroken if the next pen arrives before you inject dose four. Most people run into trouble not because the pen is short, but because they leave reordering until the pen is empty. Ordering around the time you take dose three leaves comfortable room for review and delivery.

02 · Costs and ordering

Planning the next pen and what it costs

Every pen is one four-week supply. The Mounjaro pen at the 2.5mg starting dose has a standard price of £169.99, and a new customer's first order is £40 less with code FIRST40, which is the £129.99 first-order price. If you are switching to us at a higher dose, the same first-order discount applies at any strength; for example a first 15mg order is £289.99. After that, every later order is £25 off the standard price (code DOSE25). Prices were checked 10 October 2026.

These totals are at standard prices. A new customer's first order is £40 less, and every later order is £25 less.

03 · How to order

How ordering works with EverydayMeds

Ordering takes three steps. First, complete the free online consultation, a short health questionnaire with no charge and no obligation. Second, it is reviewed by a GPhC-registered prescriber. 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 and dispatches, with same-day dispatch when you order by 3pm, and free next-day tracked delivery in temperature-controlled packaging. Saturday delivery is £14.99.

Repeat orders re-check suitability and there is no auto-shipping, so you stay in control of when the next pen is sent. We source Mounjaro directly from Eli Lilly's UK distribution through official LillyDirect supply, and ongoing monthly reviews are included. If you would rather see every option first, start from our Buy Mounjaro page.

Payment is by Visa or Mastercard, Klarna or pay-monthly options, with no subscriptions. The consultation is free and the price shown is the price paid.

04 · What the last shot is

What "the last shot" of a Mounjaro pen actually means

The last shot is the fourth and final weekly dose in a KwikPen. Mounjaro is a once-weekly injection and each pen contains four weekly doses, so one pen covers four weeks.¹ If you inject on a Monday, doses fall on four consecutive Mondays and then the pen is finished.

The fourth injection is the full, final dose the pen was made to give.

Mounjaro is the brand name for tirzepatide, made by Eli Lilly. In the UK it is licensed for weight management in adults and for type 2 diabetes, and it comes as a pre-filled multi-dose pen in six strengths: 2.5mg, 5mg, 7.5mg, 10mg, 12.5mg and 15mg.¹ The strength you hold does not change the number of doses.

Four weeks of injections, one pen. If you are on a 5mg pen, each of the four doses is 5mg. If you are on a 10mg pen, each is 10mg. Nothing about a higher strength gives you more injections.

It also helps to know where you are in the cycle. Doses one to three are straightforward for most people. Dose four is where questions arise, because the pen looks as if there is still liquid visible and the dose knob may behave differently.

If you want a related look at timing, our guides on how long one shot of Mounjaro lasts and how long a Mounjaro injection lasts cover how the medicine behaves between doses. The short version is that tirzepatide has a half-life of about five days, which is why a weekly schedule works.¹

05 · Taking dose four

How to take the fourth dose correctly

Take dose four the way you took the first three: on your usual day, at any time, with or without food. Mounjaro is injected under the skin once a week, on the same day each week.¹ There is no best time of day, because it works the same morning or evening. What matters is consistency, so pick a day and time you will remember.

Rotate your injection site. The licensed sites are the stomach area (at least 5cm from the belly button), the front of the thigh, or the back of the upper arm if someone else gives the injection.¹ If you used the left thigh last week, use another site this week.

Set the dose by turning the dose knob until the dose indicator shows the correct dose in the window. Read the number.

For the mechanics of the pen itself, such as removing the cap, attaching the needle and delivering the injection, follow the pen's instructions in the patient information leaflet supplied with your order. Follow the pen's instructions exactly for how long to hold the pen against the skin.

A practical routine for dose four:

• Check the date and confirm it is your normal injection day.
• Look at the pen label to confirm the strength matches your prescription.
• Dial to the full dose and check the number in the window.
• Choose a site you have not used for the last dose.
• Inject as the leaflet instructs, then dispose of the needle in your sharps bin. Needles and a sharps bin come with every order.

Afterwards, put the empty pen in the sharps arrangements recommended by your local pharmacy or council. Do not keep a finished pen as a spare. Once the fourth dose is in, that pen has done its job and the next pen takes over the following week.

If your next pen is a higher strength, remember your prescriber sets the pace: after at least four weeks the dose can step up, and further steps of 2.5mg follow at a minimum of four-week intervals, up to a maximum of 15mg weekly.¹

06 · When the dial stops

What to do if the dial stops early

If you are only getting three doses out of a pen, check your injection dates first, as a dose may have been logged twice or taken early.

Do not force the knob. If you believe the pen has jammed while doses should remain, keep the pen, note the lot details on the box, and contact the pharmacy that supplied it.

When you contact us, have the following ready:

• The strength and the date you started the pen.
• The dates you injected each dose.
• What the dose window showed when you tried to dial.

Support is open Monday to Friday, 9am to 5pm, by email at support@everydaymeds.co.uk, account portal chat or phone on 0333 207 0413. Our prescribing team can look at the timeline with you. Please note that dispensed prescription medicines cannot be returned except faulty, damaged or wrong items, which should be reported within 3 days of delivery, so check your pen promptly when it arrives.

If you are unsure whether a dose counted, ask the prescriber before the next injection day. For a deeper look, see our guides on why you can't get the last dose and how to get the last dose out of Mounjaro.

07 · Late or missed last dose

What if the last dose is late or missed?

If you miss a dose, take it as soon as you can within 4 days (96 hours) of the scheduled time, then carry on with your usual day.¹ If more than 4 days have passed, skip the missed dose entirely and take the next one on your normal day. You should never take two doses within 3 days of each other.

This rule applies to dose four just as it does to any other. Suppose your fourth dose was due on Monday and you remember on Thursday. That is within the 4-day window, so you can take it. Then your next dose is on your usual day. If you only remember on the following Saturday, more than 4 days have passed, so skip the missed dose and take the next one on your normal day.

Note what the rule does and does not allow. It lets you recover a late dose inside the window. It does not let you take a dose from a different pen to "catch up".

You can also change your weekly injection day if needed, as long as at least 3 days (72 hours) have passed since your last dose.¹ People often use this when the next pen arrives on a different day from their usual one. If your delivery lands midweek and you are due on Sunday, you can keep Sunday. If you want to move to a different day, count at least three days from the previous injection.

A few practical points:

• Set a phone reminder for your injection day and a second one for reordering around dose three.
• Keep a simple log of dates; our free companion app GLPTrackr (iOS and Android) tracks a GLP-1 journey.
• If a late delivery means a gap longer than 4 days, tell us so the prescriber can advise on the next step.

Switching the day is fine, but do not use it as a way to double up. The 3-day minimum between two doses is the line that keeps the schedule safe. If you are unsure which rule applies, ask before you inject, not after.

08 · Storage and in-use life

Storing the pen through to the last dose

Keep Mounjaro pens in a fridge at 2–8°C and never freeze them.¹ Once in use, a pen can be kept out of the fridge at a temperature not above 30°C for up to 30 days after first use, and must then be thrown away. A four-dose pen used weekly is finished in four weeks, so it normally sits inside that window.

Keep the pen cap on to protect it from light, and never use a pen that has been frozen.¹ If you leave the pen in a car on a hot day or put it near the freezer compartment, do not inject from it; contact the pharmacy for advice.

The 30-day figure applies to in-use pens kept not above 30°C. Figures circulating online often come from other countries' labels, so do not rely on a number you have seen elsewhere. This is especially relevant to the last shot: if a pen has been in use for many weeks because of missed doses, check the in-use date. A pen started more than 30 days ago should be thrown away.

For unopened pens, store them in the fridge until first use. They keep until the expiry date printed on the box. If an unopened pen has been out of the fridge, check with the pharmacy before using it rather than relying on a remembered day limit.¹

When you are travelling, you can fly with Mounjaro. Carry pens in hand luggage, because hold luggage can fall below freezing, ideally in a cool bag with the prescription label or a copy of your prescription.¹ In-use pens tolerate up to 30 days not above 30°C, so most holidays need no special arrangements. For hot climates, use an insulated pouch, and check destination rules for travelling with prescription injectables before you fly.

Good storage is part of getting the last shot properly. A pen that has been stored incorrectly may not be usable, and then the question is no longer how to get the last dose but how to replace it. Keep the pen in its box, in the fridge, and take it out only when you are ready to inject.

09 · Pace of results

Why finishing a pen is not the finish line

One pen is four weeks, and weight loss on Mounjaro is gradual by design. 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 Think in months, not days, and judge progress by trend rather than individual weigh-ins.

This matters for the last-shot question because the urge to squeeze more from a pen often comes from impatience or cost worry. In the SURMOUNT-1 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. Treatment works alongside a reduced-calorie diet and increased physical activity, not instead of them.

As a worked example, for someone starting at 100 kg, 20.9% is about 21 kg. That figure comes from a trial average at 15mg over 72 weeks, so it does not predict your own result.

The first weeks are also very individual. Some people notice appetite change and early loss in week one, while others feel little until a higher dose; both are normal. Early loss includes water weight, so the trend over weeks matters more than any single weigh-in. Mild nausea, altered appetite and tiredness in the first days after each injection are the commonest early effects and usually settle.¹

Your 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

So when you reach dose four, it is a checkpoint rather than an ending. It is a good moment to log how you feel, your appetite, any side effects and your weight trend, so that your monthly review has something concrete to discuss. You can also ask whether it is time to step up, hold or stay on the same dose for another pen.

10 · Dose steps between pens

Moving to the next pen: dose steps explained

Everyone starts Mounjaro on 2.5mg once a week. This starting dose is about letting your body adjust, not about weight loss itself. After at least 4 weeks the dose increases to 5mg, and can then step up by 2.5mg at a minimum of 4-week intervals (7.5mg, 10mg, 12.5mg) up to a maximum of 15mg weekly, depending on how you respond and tolerate it.¹

Because one pen is four weeks, a dose change can only come at the end of a pen, after at least 4 weeks on each dose. That is why the fourth dose is a decision point.

Many people settle at a maintenance dose of 5mg, 10mg or 15mg. Higher is not automatically better, and your prescriber will guide the right pace.¹ If you feel fine at 5mg, there is no requirement to climb the ladder.

• Pen one: 2.5mg for at least four weeks, the adjustment phase.
• Pen two: 5mg for at least four weeks.
• Pen three: 7.5mg for at least four weeks.

If you step up after 4 weeks on each of 2.5mg, 5mg, 7.5mg and 10mg, your first four pens cost £959.96 at standard prices, with a new customer's first order £40 less and every later order £25 less. Your own route may differ because the prescriber decides the pace.

If you are changing strength, order the next pen to arrive before your next injection day, not after. A pen at the new strength should be on hand when you finish dose four. Each injection should come from one pen at the dose shown in the window.

Strengths are not interchangeable by guesswork. If you are moving between strengths, confirm the new dose with the prescribing team rather than relying on the pen's appearance.

11 · NHS and private routes

NHS or private: keeping supply continuous

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 are on an NHS supply, the pen works the same way and the same four-dose limit applies. Talk to your NHS prescriber about repeat timing so you do not run out before the next pen arrives. The NHS prescription charge in England is £9.90 per item where it applies, though your own circumstances may differ.

For private supply, 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.¹ It must be used alongside a reduced-calorie diet and increased physical activity. A prescriber will assess your BMI, medical history and current medicines before deciding whether it is suitable for you.

That assessment is why repeat orders matter. With us, repeat orders re-check suitability and there is no auto-shipping. Each pen is a deliberate decision made with a GPhC-registered prescriber rather than a subscription that rolls on without review.

A few points for people moving between routes:

• If you are switching from another provider, a new customer's first order is £40 less at any dose with code FIRST40, and every later order is £25 off the standard price (code DOSE25).
• Tell the prescriber your current strength and the date of your last injection so the next pen is timed correctly.
• Do not stockpile pens to bridge a gap. Check storage rules and expiry dates first.

You can see every option on our weight loss treatments page.

Mounjaro (tirzepatide) is a prescription-only medicine, supplied only after an online consultation reviewed by a GPhC-registered prescriber. This page is information, not a substitute for medical advice.