Wegovy injections are a prescription weight loss medication that contain the molecule semaglutide, which is part of the GLP-1 class of medications. Wegovy injections are taken once a week using a pre-filled injection pen and are used to help people who are overweight or obese lose weight, in parallel with diet and lifestyle changes.

Semaglutide belongs to a group of medicines known as GLP-1 receptor agonists. These treatments mimic a natural hormone in the body that helps regulate appetite and food intake. By helping people feel fuller for longer and reducing hunger, Wegovy injections can support lower calorie intake and gradual, sustainable weight loss over time.

Weight loss injections are typically prescribed for adults with a body mass index (BMI) of 30 or above, or 27 and above where there are weight-related health conditions. Treatment should always begin with a clinical assessment to ensure the medication is safe and appropriate.

Wegovy injections contain semaglutide, a medication that mimics a naturally occurring hormone in the body called GLP-1 (glucagon-like peptide-1). This hormone plays an important role in regulating appetite, food intake, and blood sugar levels.

By activating GLP-1 receptors in the brain, Wegovy injections help reduce hunger and increase feelings of fullness after eating. Many people find they feel satisfied with smaller portions and experience fewer food cravings – or “food noise” – during treatment.

Semaglutide also slows the rate at which food leaves the stomach, which helps you stay fuller for longer, making it easier to maintain a lower calorie intake over time.

Because of these combined effects on appetite and satiety, Wegovy injections can support meaningful weight loss when used alongside healthy eating habits and increased physical activity.

Wegovy injections are available in 6 different strengths, ranging from 0.25mg to 7.2mg of semaglutide.

Patients begin with a low starting dose of 0.25 mg once per week to help the body adjust to the medication and reduce the risk of side effects. The dose is then typically increased in stages over subsequent months until a higher maintenance dose is reached, or until goal weight is achieved. At that point patients, in conjunction with their prescribing clinician, decide whether they want to stay on their current dose, titrate down, and eventually even stop taking the medication. This gradual approach allows clinicians to monitor progress and ensure the treatment remains safe and well tolerated. The image here provides typical dose titration information, but the timing and rate of dose changes vary from person to person, and should always be decided in collaboration with your prescribing clinician.

Wegovy injections are taken once a week using a pre-filled injection pen. The medication is injected just under the skin (a subcutaneous injection) and can usually be given in the abdomen, thigh, or upper arm.

Most people choose a consistent day each week to take their Wegovy injection. Your clinician will explain how to use the injection pen and how to rotate injection sites to reduce irritation.

The pen is designed to be simple to use, with a small needle and a quick injection process. Many people find that administering Wegovy injections at home becomes straightforward after the first few doses.

If you are prescribed Wegovy injections, you will receive full instructions on how to prepare the pen and administer your weekly dose safely.

You can also read our detailed guide on how to use Wegovy injections for step-by-step instructions and a video from a registered nurse.

Clinical studies have shown that Wegovy injections can support significant weight loss when used alongside diet and lifestyle changes. In large clinical trials, many people lost around 15% of their starting body weight over the course of treatment, with some individuals achieving even greater results.

Weight loss varies between individuals and depends on factors such as starting weight, lifestyle changes, and how consistently the medication is used. Wegovy injections work best when combined with long-term changes to diet, physical activity, and behaviour.

The calculator above provides an estimate based on published clinical trial outcomes, but your clinician will help determine the most appropriate treatment plan and expected progress for you.

Like all prescription medications, Wegovy injections can cause side effects. Most side effects are mild and tend to occur during the early stages of treatment as the body adjusts to the medication.

The most commonly reported side effects of Wegovy injections include:

• Nausea
• Vomiting
• Diarrhoea
• Constipation
• Headache
• Fatigue

These symptoms are usually temporary and often improve as treatment continues, particularly as doses are increased gradually over time.

More serious side effects are less common but can occur, which is why Wegovy injections should only be used following a clinical assessment and under appropriate medical supervision. For more detailed safety information, you can read our full guide to Wegovy injection side effects.

Wegovy injections are started at a lower dose and increased gradually to help reduce the risk of side effects while the body adjusts to treatment.