Mounjaro must-haves: the decisions that shape your treatment

Keeping it cold, and what happens when you can't

Mounjaro's KwikPen needs to be refrigerated between 2°C and 8°C. Most people find the fridge door works well, easy to see, easy to remember. If you're away from home, or the pen has accidentally been left out, the rules around room-temperature storage are specific enough that copying them from memory is risky. The Mounjaro SmPC on the eMC gives the exact permitted window; that's the place to check, not a forum post.

Pens should never be frozen, and the needle should be attached only immediately before injecting, not stored with one already in place. Injection sites rotate between the abdomen, thigh, and upper arm; using the same spot repeatedly can cause local reactions that slow absorption. These are small habits, but they add up to consistent results.

If you're heading away and want to know how travel affects your schedule, our page on taking a week off Mounjaro covers the clinical picture.

What to eat, and why under-eating is the underrated risk

Appetite on Mounjaro can fall sharply, especially after a dose increase. That's the point, clinically speaking, but it creates a practical trap. When meals feel unappealing, it's easy to skip protein, skip vegetables, and end up running on very little. Over time, inadequate protein alongside rapid weight loss can mean losing muscle alongside fat, which most people don't want.

There's no single correct diet on Mounjaro; the licence is clear that treatment works alongside a reduced-calorie diet and increased physical activity, and the specifics are for you and your clinical team to shape. As a rough guide, prioritising protein at each meal (eggs, fish, chicken, legumes) and keeping up fluid intake tends to help with both the side-effect profile and body composition. The NHS healthy weight guidance is a reasonable starting point for general principles.

Strength exercise alongside treatment is worth discussing with your prescriber too. It's not a requirement, but it's something many people on treatment find genuinely useful for how they feel day to day.

Managing side effects without abandoning treatment early

Gastrointestinal side effects (nausea, loose stools, constipation, reflux, burping) are the most common reason people consider stopping before they've given treatment a fair chance. They're real, they're sometimes unpleasant, and they usually settle within a week or two of a new dose. The MHRA also flagged acute pancreatitis as a known but infrequent side effect in its January 2026 Drug Safety Update: if you develop severe, persistent stomach pain that radiates to the back, seek urgent medical attention. That's a different picture from ordinary treatment nausea and shouldn't be managed at home.

Smaller, lower-fat meals around injection day, eating slowly, and avoiding alcohol tend to ease the GI effects for most people. If symptoms feel unmanageable, the right move is to contact your prescriber, not to skip doses unilaterally. Our FAQs cover several of the most common side-effect questions, and our aftercare team is available seven days a week if something comes up between reviews.

People with pre-existing gut conditions sometimes wonder whether Mounjaro is appropriate for them at all. If that's your situation, the page on Mounjaro and IBS is worth reading before your consultation.

Prescriptions, repeats, and staying on track clinically

Mounjaro is a prescription-only medicine. A prescriber decides whether it's suitable for you, reviews your progress before every repeat, and manages any dose changes. That clinical oversight isn't a formality, it's the mechanism that keeps treatment safe, catches problems early, and ensures your dose reflects where you actually are rather than where a schedule says you should be.

At nume, there are no subscriptions and no automatic renewals. Every repeat order is reviewed by a prescriber before it's dispensed from our GPhC-registered pharmacy (registration number 9012878, verifiable on the GPhC register). If you order before 12pm on a working day and your prescription is approved, it goes out the same day with DPD, next working day, tracked, in plain packaging.

Eligibility covers adults with a BMI of 30 or above, or 27 or above with a weight-related condition such as high blood pressure, high cholesterol, or type 2 diabetes. BMI alone doesn't guarantee approval; the whole picture matters, which is why checking whether Mounjaro is right for you is a useful first step. For context on what treatment costs through a private pharmacy, the Mounjaro cost page explains the components honestly. And if you'd like to understand the clinical science in more depth, the tirzepatide overview covers the mechanism, trial evidence, and NICE position in full. If you're specifically interested in how the Voi Mounjaro programme works, that page sets out the details clearly.

When you're ready, you can start your free consultation and have your answers reviewed by a prescriber the same day.