Wegovy (Semaglutide)

To be eligible for a Wegovy prescription, you must meet certain criteria of either:

• a BMI of 30 or higher
• a BMI of 27 or higher if you also have a pre-existing medical condition that is affected by your weight, such as cardiovascular disease or high blood pressure

Wegovy is not suitable for everyone. You should not take Wegovy if you are:

• allergic to Wegovy’s ingredients
• pregnant, or planning to become pregnant
• breastfeeding

If you are considering requesting treatment for Wegovy and have pancreas or heart problems, your doctor will assess whether Wegovy is suitable for you and your medical conditions. You can obtain a prescription for Wegovy if your doctor agrees it is suitable for you.

Wegovy contains semaglutide, a man-made version of a natural hormone called glucagon-like peptide-1 (GLP-1). After eating, our bodies release this hormone to help regulate blood sugar levels. It also sends a message to the brain that you’re full. By mimicking this hormone, Wegovy gives you the same feeling of being full and satisfied when eating less food.

You’ll be advised to follow a healthy diet and adopt regular exercise by your doctor in order for you to get the most out of Wegovy.

Wegovy is injected under the skin once a week with or without food. You should try to take it at the same time each week. Each Wegovy pen has 4 doses and lasts for 4 weeks of treatment, then you'll need to start a new pen.

Always double-check you have the correct dose prescribed and have the right medication before injecting, if you also use other injectable medications.

➤ Read more about how to inject Wegovy safely.

Taking your Wegovy injection

Ensure you read the Wegovy patient information leaflet for full instructions and diagrams and follow any additional doctor’s advice. The steps below are a general guide and do not replace this information.

1. Check the name and dose of your Wegovy pen to ensure it matches your prescription request, and check that it is the right medication and dose.
2. Remove the pen cap and check the liquid is clear and colourless.
3. Use a new needle for each weekly dose.
4. Attach and secure the needle.
5. Remove the outer and inner needle cap, and perform a flow check of the pen as per the leaflet instructions (this only needs to be done when using the pen for the first time).
6. Set the dose on your pen by turning the dose selector until the correct dose is showing.
7. Select your skin injection site (e.g. thighs, abdomen).
8. Insert the needle into the skin at a straight angle, as shown in the diagram in the patient information leaflet. You should be able to see the dose counter.
9. Remove the needle and carefully replace the outer needle cap.
10. Unscrew the needle and dispose of the 2 together in a sharps bin.
11. If there are still doses left in your pen, place the pen cap back on, and safely store it for future use.
12. Log your Wegovy dose so you remember when your last dose was.
13. Set a reminder for your next dose, Wegovy is best taken at the same time each week.

Wegovy is not an addictive medication so you shouldn’t get withdrawal symptoms. It is therefore safe to stop Wegovy whenever you need to without reducing your dose beforehand. However, stopping Wegovy suddenly may lead to weight gain, so it’s advisable to speak to your doctor before stopping.

What if I miss a dose of Wegovy?

If you forget to take Wegovy and it has been 5 days or less since it was due, you can take Wegovy as soon as you remember. Take your next dose on your usual injection day, even if this means you are taking your next dose within 2 or 3 days.

If you have missed a dose of Wegovy and it has been longer than 5 days since your dose was due, skip your missed dose. You can then continue your treatment when your next dose is due. Never take a double dose, as this can increase your risk of side effects.

Regularly missing doses may affect the results of your treatment. If you have missed 2 doses or more, speak to your doctor, as you may need to restart your treatment at a lower dose. This is particularly important if you usually get gastrointestinal side effects when increasing your dosage.

In 3 clinical trials, Wegovy was found to be an effective medication for weight reduction.

The 68-week trial carried out on Wegovy found that patients using the 2.4 mg maintenance dose achieved, on average, a change in body weight of 14.9% (compared to 2.4% in the placebo group). Both groups followed a reduced-calorie diet and increased physical activity.

Of all the people taking Wegovy:

• almost 85% achieved weight loss of at least 5%
• 66% achieved weight loss of at least 10%
• almost 50% achieved weight loss of at least 15%

Very common side effects of Wegovy include:

• headache
• diarrhoea
• constipation
• nausea or vomiting (feeling or being sick)
• feeling weak or tired
• stomach pain

These side effects go away over time and once your body gets used to the medication. You are given Wegovy gradually to reduce the risk and severity of these side effects.

Common side effects of Wegovy include:

• upset stomach or indigestion
• dizziness
• burping or gas (flatulence)
• bloating
• reflux or heartburn
• hair loss
• reactions at the injection site, such as redness, swelling, or soreness
• gallstones
• inflamed stomach (gastritis), which can cause nausea, vomiting, and stomach ache
• hypoglycemia (low blood sugar) in patients with diabetes, which is more likely if you’re taking sulfonylurea or insulin
• a change in the way food or drink tastes
• a change in skin sensations

Uncommon side effects of Wegovy include:

• fast heartbeat
• an increase in pancreatic enzymes, which will show up in blood tests
• delayed gastric emptying (gastroparesis)
• hypoglycemia in people without diabetes
• an increased level of bilirubin in the blood which can cause jaundice – symptoms include yellowing of the whites in your eyes and skin

Wegovy also has some serious side effects, which should be treated straight away:

• In diabetic patients, a common serious side effect is complications of diabetic eye disease (diabetic retinopathy). If you have diabetes you should inform your doctor if you experience eye problems, such as changes in vision, during treatment with this medication.
• An uncommon serious side effect is an inflamed pancreas (acute pancreatitis). If you have long-lasting and severe pains in your stomach or back, speak to your doctor straight away or call 999.
• Another uncommon and serious side effect is the development of kidney or bladder stones. Symptoms include a change in urine colour or difficulty urinating and lower abdomen or back pain.
• A rare serious side effect of Wegovy is a severe allergic reaction. You must call 999 or get to A&E straight away if you have breathing problems, wheezing, difficulty swallowing, swelling in your face and throat, dizziness or weakness.
• Another rare and serious side effect is that Wegovy may increase the risk of fractures, including hip fractures. You should attend A&E or call 999 straight away if you think you’ve fractured a bone.
• A serious side effect (there currently isn’t enough data available to know how often it occurs) is bowel obstruction. This is a severe form of constipation with other symptoms such as stomach ache, vomiting and bloating.

You can find out more about the side effects of Wegovy in your patient information leaflet.

Wegovy can interact with other medications, so it’s important to tell your doctor what you’re currently taking before starting treatment. Your doctor may change the dose of your other medications whilst taking Wegovy to make sure it’s safe for you to take.

Wegovy interacts with insulin and sulfonylureas, which are both treatments for type 2 diabetes. Taking Wegovy with one of these medications can increase the risk of low blood sugar levels.

You should never use Wegovy with another medication that contains a GLP-1 receptor agonist, such as liraglutide or Mounjaro. This is the same as taking a double dose and could increase the risk of serious side effects.

Who can take Wegovy?

Note – you should not take Wegovy if:

• you are pregnant or trying to conceive
• you are breastfeeding
• your BMI is below 30 and you don’t have a weight-related medical condition
• you have ever had a serious allergic reaction to any of the ingredients in Wegovy, especially semaglutide

Wegovy is also cautioned in some people, such as those with:

• diabetic retinopathy
• a history of pancreatitis
• severe, congestive heart failure

You should speak to your doctor before using Wegovy pens if you have:

• kidney problems
• diabetes
• inflammation of your pancreas
• low blood sugar levels (hypoglycaemia)
• diabetic eye disease (retinopathy)

A doctor may not be able to prescribe Wegovy in these cases. Similarly, if you’re taking another GLP-1 receptor agonist or another medication that can interact with Wegovy, you may not be able to take it. Speak with your doctor about all your health conditions and medications you take before starting treatment.

Wegovy and Mounjaro are both injectable weight loss medications. The main difference between Wegovy and Mounjaro is the active ingredient. They both contain GLP-1 receptor agonists, but Wegovy contains semaglutide and Mounjaro contains tirzepatide. They both work in a similar way, but tirzepatide (Mounjaro) also mimics a second hormone, known as glucose-dependent insulinotropic polypeptide (GIP).

What is the difference between Wegovy and Saxenda (Liraglutide)?

Saxenda and Wegovy are both injectable weight loss medications that contain different active ingredients. Saxenda also contains a GLP-1 receptor agonist called liraglutide. They both work in the same way to make you feel fuller for longer after meals. Saxenda is taken once a day, but Wegovy is a once-weekly injection. Saxenda is currently long-term out of stock, but generic liraglutide with the name Nevolat is available in the UK.

What is the difference between Wegovy and Ozempic?

Ozempic and Wegovy are the same medication but they are used to treat different health conditions. Ozempic is used to improve blood sugar levels in adults who have type 2 diabetes, whereas Wegovy is used for weight loss. Both medications contain the same active ingredient, semaglutide. The strength of the medication in Ozempic is different to Wegovy, so you should only use these treatments as recommended by your doctor.