Mounjaro, Ozempic, and Wegovy. What are they?

You may have heard about Mounjaro, Ozempic, and Wegovy on social media or from someone who has lost weight. But what do these medicines actually do, and are they suitable for everyone?

They are prescription medicines that can help control blood sugar, appetite, or both. Ozempic and Wegovy contain the same medicine, called semaglutide. Mounjaro contains a different medicine, called tirzepatide. Choosing one starts with a medical assessment, rather than a brand name. [1,2,3]

This guide focuses on the once-weekly injections for adults. Tablet versions of some brands are available in certain countries and have different instructions. Approved uses, strengths, devices, and availability vary by country. An overseas approval does not establish approval or availability in Ghana. [1,2,3]

How do they work?

After you eat, your gut sends messages to your brain and other organs. Some of these messages help you feel full. Others help your body manage the sugar entering your bloodstream.

These medicines copy some of those natural messages. They can help you feel less hungry, feel full sooner, and eat smaller portions. They also help the body release insulin when blood sugar is high. Insulin is the hormone that helps sugar move from your blood into your cells. These medicines are not insulin. [1,3,4]

Semaglutide acts on a signal called GLP-1. Tirzepatide acts on GLP-1 and a second signal called GIP. You do not need to remember the names: the practical point is that the medicines help regulate appetite and blood sugar. They also slow the movement of food out of the stomach. [1,3,4]

What is Mounjaro?

Mounjaro is the brand name for tirzepatide. It is injected once a week and helps treat type 2 diabetes. It can also lead to substantial weight loss. [3]

Its weight-management approval depends on the country. For example, Mounjaro is licensed for weight management in eligible adults in the UK. In the United States, tirzepatide is marketed for weight management under the separate brand name Zepbound. These names should not be treated as separate medicines to take together. [3,5,6]

Acting on two signals does not mean that Mounjaro is automatically the best choice for every person. Your health, other medicines, side effects, and the locally authorised product all matter.

Product photograph: official Mounjaro image on the Eli Lilly patient website (image: Eli Lilly and Company). Shown as a link because publication permission for the manufacturer's photograph has not been confirmed. Packaging and devices vary by country; a photograph does not establish authenticity, and the strength shown there is an identification example, not a recommended dose.

What is Ozempic?

Ozempic contains semaglutide. Its injection is used to treat adults with type 2 diabetes, alongside eating well and being physically active. It also has approved heart and kidney benefits for certain people with type 2 diabetes. [1]

People may lose weight while using it, but Ozempic is not the brand specifically licensed for weight management in the US. A doctor may sometimes prescribe a medicine outside its approved use; this is called off-label prescribing. It requires a clear medical reason and a discussion of the benefits and risks. [1,6]

Product photograph: official Ozempic images in the Novo Nordisk media library (image: Novo Nordisk). Shown as a link because publication permission for the manufacturer's photograph has not been confirmed. Labels, strengths, and packaging vary; the strength shown there is not a recommended dose.

What is Wegovy?

Wegovy also contains semaglutide, but it is specifically licensed for weight management in eligible people, together with a reduced-calorie eating plan and physical activity. It also has additional approved uses in certain patient groups. [2]

Although Ozempic and Wegovy share an ingredient, their approved uses, strengths, and instructions differ. Do not take them together or switch between them yourself. [1,2]

Product photograph: official Wegovy images in the Novo Nordisk media library (image: Novo Nordisk). Shown as a link because publication permission for the manufacturer's photograph has not been confirmed. The manufacturer's group photograph includes strengths that may not be available or authorised in Ghana; it is not a dosing schedule or a complete guide to every product format.

The main differences at a glance

All three injection products discussed here are used once weekly. They are not interchangeable milligram for milligram. [1,2,3,5]

Who might benefit from weight-management medicine?

These medicines are generally considered when excess weight is affecting health. Common adult eligibility criteria include a BMI of 30 or above, or 27 or above with a weight-related condition, such as high blood pressure or type 2 diabetes. BMI compares your weight with your height. It is one part of the assessment, not the whole decision. Local guidance and the particular medicine also matter. [5,6]

They are not intended simply to help someone of a healthy weight lose a few kilograms for an event. A doctor should assess the likely benefit, possible harm, and alternatives. [6]

How are the injections used?

The medicine goes under the skin, usually in the tummy, thigh, or upper arm. A clinician should show you how to use your exact device. Some pens contain one dose; others contain several doses for one person. Never share a pen, even if the needle is changed. [1,3,4]

Treatment usually begins with a low dose, which may be increased gradually. This helps your body adjust. Do not copy a friend's dose, count pen clicks to invent a dose, combine these medicines, or increase your dose to speed up weight loss. Ask your prescriber what to do after a missed dose or a break in treatment. [1,2,3]

What results should I expect?

Appetite may change before you notice much change on the scale. Weight loss takes time, and results differ. Your doctor should review your progress, nutrition, side effects, and blood sugar where relevant. A bigger dose is not automatically better for you. [3,6]

Treatment may be long term. Hunger can return and weight can come back after stopping. Discuss a maintenance plan before starting, including ongoing costs and what happens if treatment becomes unavailable. [6]

What side effects should I know about?

Common problems include feeling sick, vomiting, diarrhoea, constipation, tummy discomfort, and indigestion. They can be more noticeable when starting treatment or increasing the dose. [1,3]

Smaller meals, eating slowly, and avoiding very fatty meals may help. Drink fluids regularly, within any fluid limit your doctor has given you. Contact your prescriber if symptoms persist, interfere with eating, or make it difficult to drink. [7]

Low blood sugar is a particular concern when these medicines are combined with insulin or certain diabetes tablets. Your doctor may need to adjust those treatments. [3]

Who needs extra care?

Tell your doctor about previous pancreatitis, gallstones, kidney problems, diabetes-related eye disease, or severe stomach-emptying problems. Also disclose any personal or family history of medullary thyroid cancer, a specific type of thyroid cancer, or MEN2, an inherited hormone-gland condition. US labels prohibit use in people with either of these histories. Thyroid tumours occurred in animal studies; whether these medicines cause this cancer in humans is unknown. [1,2,3]

Pregnancy and breastfeeding: Do not use these medicines for weight loss during pregnancy. Discuss pregnancy plans and breastfeeding before treatment. Semaglutide should be stopped at least two months before a planned pregnancy; UK tirzepatide guidance specifies at least one month. Arrange this with your prescriber, particularly if you have diabetes. [1,2,5]

Contraception: Mounjaro can reduce the reliability of the contraceptive pill. Use an additional barrier method, such as condoms, or switch to a suitable non-oral method for four weeks after starting and four weeks after each dose increase. Discuss the plan with your clinician. [3]

Surgery and sedation: Tell your surgeon and anaesthesia team that you take one of these medicines. Slower stomach emptying can affect procedure safety. They will give you an individual plan. [1,3]

Eating well still matters

Eating less should not mean missing out on nourishment. Include protein foods such as fish, eggs, chicken, beans, or lentils, together with vegetables and suitable portions of starchy foods. Familiar meals can be adapted: for example, add vegetables and fish or beans while adjusting your portion of rice, yam, banku, or kenkey. [8]

Regular activity and strength exercises help protect muscle during weight loss. Choose activities appropriate for your health and ability, and ask for nutrition support if your appetite becomes too small to eat well. [8]

Buying and storing your medicine safely

Use a licensed pharmacy and a valid prescription. Fake Ozempic products have been reported internationally. A familiar-looking pen or box does not prove that a medicine is genuine. Ask your pharmacist to verify the product and its supply source. [9]

Follow the storage instructions for your exact product. Avoid freezing it, leaving it in a hot car, or exposing it to direct sunlight. Refrigeration and permitted time outside the fridge differ between products and devices. [1,3,4]

Start with a conversation about your health

If you are considering medical weight management, book a consultation with Elixir Clinic in East Legon, Accra. Bring a list of your medicines and any recent test results. Discuss your health history, goals, and whether a prescription treatment is appropriate for you.

This article provides general education for adults. It does not replace a personal medical assessment or the leaflet supplied with your medicine. Product photographs are linked to their official manufacturer pages rather than displayed here, because publication permission has not been confirmed; packaging and devices may vary by country, and a photograph does not establish authenticity or suitability.

Sources and further reading

Information checked on 14 October 2026. The supplied Elixir Clinic GLP-1 information sheet informed the explanation; current official sources were used to check product differences and safety information.

1. Novo Nordisk: Ozempic injection prescribing information

2. Novo Nordisk: Wegovy prescribing information

3. Eli Lilly: Mounjaro prescribing information and medication guide

4. NHS: Semaglutide

5. Eli Lilly UK: Mounjaro KwikPen product information

6. NIDDK: Prescription medications to treat overweight and obesity

7. Guy's and St Thomas' NHS Foundation Trust: Managing side effects with diet

8. Cambridge University Hospitals: Dietary advice for people using tirzepatide

9. World Health Organization: Medical Product Alert No 2 of 2024 on falsified Ozempic