Moving from 5mg to 7.5mg Mounjaro: what getting your next dose actually involves

Picture where you are right now: four weeks at 5mg, ready for the next step

Most people reaching this point have managed the 5mg pen without serious trouble and are wondering whether moving up will accelerate their progress. It's a reasonable question, and your instinct to ask before acting is the right one. The Mounjaro KwikPen is a pre-filled, single-strength device: the 5mg pen has been manufactured and calibrated to deliver exactly 5mg per injection. There is no dial, no adjustable mechanism, no way to draw more than the pen contains. Attempting to modify or combine doses would be unsafe, and frankly unnecessary, because the licensed process for moving up is straightforward when done properly.

Tirzepatide's dosing schedule is designed to step up in 2.5mg increments, typically every four weeks, as the NHS tirzepatide medicines page confirms. Each strength exists as its own pen. Getting 7.5mg therefore means one thing: a new prescription for the 7.5mg pen, written after a clinical review that confirms the increase is appropriate for you. That review protects you, some people need more time at 5mg, others have developed side effects that change the picture, and a prescriber needs to know both before writing the next script.

Some readers arrive here from the opposite direction, having been dispensed a 7.5mg pen and wondering about extracting a 5mg dose from a 7.5mg pen. The same principle applies: the pen is pre-set, and the answer is to obtain the correct-strength pen rather than attempt any modification. Others ask about getting 3.75mg from a 5mg pen, or about getting 5mg out of a 7.5mg pen, and in every case the guidance is the same: work with your prescriber to get the right pen for your dose rather than modifying what you have.

The legal route to a 7.5mg Mounjaro prescription in the UK

Mounjaro is a Prescription-Only Medicine regulated by the MHRA. The only lawful way to obtain it is through a registered prescriber following a clinical assessment, full stop. If you're already on treatment through a legitimate service, your next step is a repeat consultation where your prescriber reviews how you've responded and decides whether a dose increase is clinically appropriate.

For a private route, a regulated online pharmacy is one option. Before using any online pharmacy, it's worth spending thirty seconds verifying it: check the GPhC pharmacy register to confirm the service holds a valid premises registration. Legitimate pharmacies dispense only on a valid prescription and source through the authorised UK supply chain, they do not offer Mounjaro pens without a prescription, or at prices that sit dramatically below the rest of the market.

The MHRA has issued clear public warnings about counterfeit weight-loss pens circulating online, including fake tirzepatide pens seized in UK raids. Buying from unverified social-media sellers, or being offered a pen without any clinical check, is a significant safety risk. You can report suspect sellers via the MHRA Yellow Card scheme. A discount code from an unknown seller is a red flag, not a saving.

Your GP is another avenue worth exploring. Getting Mounjaro through a GP is possible for some patients, though NHS eligibility criteria are strict and phased, and availability varies by practice and area. If you are already on private treatment, transferring your care or continuing with a private prescription remains a straightforward option.

How a dose review works at nume, and what arrives

At nume, every repeat order triggers a proper clinical re-review. You update your prescriber on how the 5mg pen has gone (weight change, any side effects, how you've been tolerating the injections) and a GPhC-registered Independent Prescriber assesses whether 7.5mg is the right next step. That assessment happens the same day. No queues, no algorithm making the call.

If the prescriber approves, the new pen is dispatched from our GPhC-registered pharmacy. Order by 12pm and it ships the same working day. The following morning, a DPD tracking notification lands on your phone, and by the afternoon your 7.5mg pen arrives in a plain, sealed box, nothing on the outside identifying the contents. The pen itself is the standard Mounjaro KwikPen format: pre-filled, ready to use, with four weekly doses at the prescribed strength.

Our full Mounjaro guide covers the injection schedule, storage, and what to expect at each dose. It also includes guidance for people moving from 7.5mg to a 10mg dose, for those planning further ahead in the titration schedule. For a broader look at weight-loss treatment options, the weight-loss treatments overview sets out how the medicines compare and what eligibility looks like across the range.

Who qualifies for Mounjaro, and what the 7.5mg step requires

The licensed eligibility for Mounjaro in the UK is broadly: adults aged 18 or over with a BMI of 30 or above, or 27 or above alongside at least one weight-related condition such as high blood pressure, raised cholesterol, type 2 diabetes, or obstructive sleep apnoea. Lower BMI thresholds may apply for some ethnic backgrounds under NICE's appraisal of tirzepatide (TA1026). A prescriber will also consider your full medical history, any medicines you take, and whether the previous dose was tolerated before agreeing to increase.

You don't need to have reached a particular weight-loss target to move to 7.5mg. The increase is a clinical decision, not a reward for results. Some people move through the schedule steadily; others stay at a given dose longer because it's working well or because their body needs more adjustment time. The prescriber's role is to judge which applies to you.

If you're not yet on treatment and want to understand the full picture before starting, how to buy Mounjaro through a legitimate UK service covers the process from eligibility check to first pen. Our clinical team profile is at the prescriber page if you'd like to know more about who reviews your care.