> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hi-doctor.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Tirzepatide (Mounjaro) for weight management

> How tirzepatide's dual GIP/GLP-1 action works, its weekly dose escalation, EU authorisation, and SURMOUNT-1 side effects.

Tirzepatide is a medicine given as an injection under the skin once a week. It acts on two natural gut-hormone signals at once, GLP-1 and GIP, which together lower appetite and slow how fast food leaves the stomach, so people usually eat less. In the EU it is sold as **Mounjaro**.

## What it is

<Info>
  **Active ingredient:** Tirzepatide · **Dosages:** 2.5 – 15 mg / week
</Info>

Tirzepatide is a long-acting GIP and GLP-1 receptor agonist, given as a pre-filled injection pen. It is a dual receptor agonist — it acts on the GLP-1 and GIP gut-hormone receptors at the same time — and in clinical trials this translates into larger average weight loss than mono-agonist GLP-1 medicines in adults with obesity. It is indicated for adults who meet the BMI criteria for weight management, and for type 2 diabetes.

## How it works

<CardGroup cols={3}>
  <Card title="Copies two gut hormones" icon="atom">
    Tirzepatide activates the receptors for two natural gut hormones, GIP and GLP-1, which the body releases after eating. The EU product information describes it as a long-acting GIP and GLP-1 receptor agonist that binds both receptors with high affinity.
  </Card>

  <Card title="Turns down appetite signals" icon="battery-full">
    It switches on two gut-hormone receptors at the same time, which together reduce appetite and slow how quickly the stomach empties.
  </Card>

  <Card title="Slows the stomach, steadies glucose" icon="stomach">
    Tirzepatide delays gastric emptying, so food leaves the stomach more slowly after a meal. It also increases insulin release in a glucose-dependent way and lowers glucagon. The weight change comes mainly from eating less, and is mostly a loss of fat mass.
  </Card>
</CardGroup>

## Dose schedule

<Steps>
  <Step title="Weeks 1–4 — 2.5 mg starting dose">
    Once weekly, on the same day each week.
  </Step>

  <Step title="From week 5 — step up every 4 weeks as tolerated">
    Injection under the skin, once a week.
  </Step>

  <Step title="Month 4+ — personalised maintenance dose">
    The doctor reviews your response every 3 months and decides with you whether to continue, adjust or stop. Discontinuation is gradual and paired with a maintenance plan.
  </Step>
</Steps>

## EU authorisation

Tirzepatide has been authorised for use in the EU since **11 December 2023**. It was first authorised in September 2022 for type 2 diabetes, and its licence was extended on 11 December 2023 to cover weight management alongside a reduced-calorie diet and more physical activity.

* **EMA EPAR — Mounjaro (tirzepatide)**
* **EMA — Mounjaro procedural steps**: variation II/0007, extension of indication to chronic weight management; CHMP opinion 09/11/2023, Commission Decision 11/12/2023
* **EMA variation assessment report — Mounjaro II/0007** (EMA/539700/2023)
* **SURMOUNT-1** — *N Engl J Med* 2022;387(3):205-216
* **ClinicalTrials.gov — NCT04184622** (SURMOUNT-1)

## What has been reported

Figures below are the treatment-regimen estimand at week 72 of SURMOUNT-1. People with type 2 diabetes were excluded, everyone also received diet and exercise counselling, and the trial did not follow weight after treatment stopped.

| Effect                                | 5 mg  | 10 mg | 15 mg | Placebo |
| ------------------------------------- | ----- | ----- | ----- | ------- |
| Nausea                                | 24.6% | 33.3% | 31.0% | 9.5%    |
| Diarrhoea                             | 18.7% | 21.2% | 23.0% | 7.3%    |
| Constipation                          | 16.8% | 17.1% | 11.7% | 5.8%    |
| Vomiting                              | 8.3%  | 10.7% | 12.2% | 1.7%    |
| Hair thinning (alopecia)              | 5.1%  | 4.9%  | 5.7%  | 0.9%    |
| Stopped treatment due to side effects | 4.3%  | 7.1%  | 6.2%  | 2.6%    |

Acute pancreatitis was independently confirmed in 3 people on tirzepatide and 1 on placebo across the SURMOUNT-1 safety dataset reviewed by the EMA.

<Warning>
  Severe stomach pain that does not go away can signal pancreatitis and needs prompt assessment.
</Warning>

## How Hi-Doctor handles it

By activating two receptors at once, tirzepatide reinforces satiety signals, slows stomach emptying and helps regulate the insulin response. It's a chronic treatment for as long as it's beneficial and safe — the doctor reviews your response every 3 months. An EU-licensed doctor reviews your case and, if eligible, issues an electronic prescription valid at any EU pharmacy under Directive 2011/24/EU. See [pricing](/essentials/pricing) for the current consultation fee — the medicine itself is paid separately at a pharmacy.

## Related reading

* [Saxenda (liraglutide)](/library/medicines/saxenda) — a daily GLP-1 alternative
* [Overweight](/library/conditions/overweight) — when a medical approach makes sense
* [Weight regain after dieting](/library/conditions/weight-regain) — a related condition Hi-Doctor reviews
* [How a consultation works](/essentials/how-it-works)
* [Semaglutide (Wegovy)](/library/medicines/semaglutide)
* [Obesity](/library/conditions/obesity)
* [Safety and eligibility](/essentials/safety)

## Common questions

<AccordionGroup>
  <Accordion title="How does tirzepatide work?">
    Tirzepatide is a dual receptor agonist. It activates the receptors for two natural gut hormones, GIP and GLP-1, which the body releases after eating. The EU product information describes it as a long-acting GIP and GLP-1 receptor agonist that binds both receptors with high affinity.
  </Accordion>

  <Accordion title="How is tirzepatide dosed?">
    It is given as one injection under the skin once a week. The starting dose is 2.5 mg for the first 4 weeks, then the dose steps up every 4 weeks as tolerated. The doctor reviews your response every 3 months and decides with you whether to continue, adjust or stop.
  </Accordion>

  <Accordion title="What are the most common side effects?">
    In SURMOUNT-1, nausea was reported by up to 33.3% of participants, diarrhoea by up to 23.0%, constipation by up to 17.1%, and vomiting by up to 12.2%. Acute pancreatitis was independently confirmed in 3 people on tirzepatide and 1 on placebo.
  </Accordion>

  <Accordion title="Is tirzepatide authorised in the EU?">
    Yes. Tirzepatide has been authorised for use in the EU since 11 December 2023 for chronic weight management alongside a reduced-calorie diet and more physical activity.
  </Accordion>

  <Accordion title="What happens when you stop tirzepatide?">
    The trial did not follow weight after treatment stopped. The doctor recommends gradual discontinuation paired with a maintenance plan.
  </Accordion>
</AccordionGroup>

## Start a consultation

<Card title="Weight-loss consultation" icon="stethoscope" href="https://hi-doctor.ai/consultation/weight-loss/1">
  Answer the weight-loss questionnaire and a registered doctor reviews it.
  They decide whether treatment is appropriate, which one, and at what dose —
  and declining is a normal outcome. See [what it costs](/essentials/pricing)
  and [how the review works](/essentials/how-it-works).
</Card>

<Warning>
  This page is reference information, not medical advice and not a prescription.
  Whether a medicine is appropriate for you is decided by a registered doctor
  after reviewing your consultation.
</Warning>