Mounjaro isn't one dose — it's a ladder you climb slowly. Here's how the steps work, why you start low, and what each stage feels like, in plain English.
Mounjaro (tirzepatide) is stepped up gradually. You start at 2.5 mg once a week for four weeks, then move to 5 mg. From there the dose can rise in 2.5 mg increments — 7.5 mg, 10 mg, 12.5 mg — up to a maximum of 15 mg once weekly, with at least four weeks between each increase.
It's one injection a week, on the same day each week, at whatever time suits you. The point of the ladder is tolerability: raising the dose slowly is how the medicine is designed to be manageable, rather than overwhelming your body all at once.
The 2.5 mg you start on isn't really a "weight-loss dose" — it's a settling-in dose. It gives your gut time to adjust to the medicine, which is what keeps early side effects (usually mild nausea, or feeling full quickly) to a minimum. People who rush the ladder tend to feel rougher without losing any faster. Start low, go slow is the whole design.
At least four weeks. You hold 2.5 mg for the first four weeks, and any later increase is spaced at least four weeks apart so your body can settle at each level first.
Crucially, the top of the ladder isn't the goal for everyone. Plenty of people do well and stay on a lower maintenance dose (often 5 mg or 10 mg) long-term because it's working and feels comfortable. The right dose is the lowest one that gives you a good result — not automatically 15 mg.
No — never adjust your own dose. Stepping up is a clinical decision made at review, based on how you're tolerating the medicine and how you're responding. Going up too fast makes side effects worse without any extra benefit.
If your current dose feels wrong — too much nausea, or you feel it's not doing enough — that's exactly the conversation to have with the pharmacist at your review, not something to change on your own.
Most side effects are digestive — nausea, feeling full quickly, sometimes constipation or loose stools — and they're usually worst in the few days after a dose *increase*, then settle. Eating smaller portions, slowing down at meals, and staying hydrated all help. Anything severe or persistent (ongoing vomiting, severe stomach pain) is a reason to stop and contact us or a doctor. We cover this in detail in our side-effects guide.
Our pharmacist manages your dose ladder with you: scheduled reviews, side-effect support, and a sensible pace. The consultation is free — you only pay for treatment if it's right for you.
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