Question 1

Accepted Answer

GLP-1 (glucagon-like peptide-1) is a hormone that your body naturally releases from the gut after you eat. It acts on receptors throughout the body, helping to regulate appetite and blood sugar. One of its main roles is to signal to your brain when you've had enough to eat.
Natural GLP-1 is broken down within a few minutes. GLP-1 weight loss medications are designed to mimic this hormone but last much longer, allowing them to work throughout the day.
These medications help by:
•	Reducing appetite, so you feel less hungry.
•	Increasing feelings of fullness, helping you eat smaller portions.
•	Slowing stomach emptying, so you stay satisfied for longer after meals.
•	Reducing food cravings, making it easier to stick to healthier eating habits.
•	Helping regulate blood sugar, by improving the body's natural response after eating.
As well as supporting significant weight loss, clinical studies have shown that GLP-1 medications can also improve overall health. Benefits may include a lower risk of heart disease, improvements in blood pressure and blood sugar control, and reduced fat build-up in the liver (fatty liver disease).
These medications work best when combined with healthy lifestyle changes, including a balanced diet and regular physical activity.

Question 2

Accepted Answer

Most people tolerate GLP-1 medications well, experiencing either no side effects or only mild side effects while taking GLP-1 weight loss medication.

Around 30–50% of people experience some gastrointestinal side effects, such as nausea, constipation, diarrhoea, bloating, indigestion or vomiting, particularly when starting treatment or increasing the dose.

For most people, these side effects are mild to moderate, improve within a few weeks, and can often be managed by increasing the dose gradually and following dietary advice.

Only around 4–8% of patients stop treatment because of side effects in clinical trials.

You can minimise side effects, by eating smaller meals, avoiding high-fat or high-carbohydrate meals, staying well hydrated, and increasing your dose gradually and only if needed/advised by your clinician. If side effects do occur, they can often be managed with simple measures or by adjusting your treatment plan.

Less common but important side effects include:

Gallstones or gallbladder inflammation, particularly with rapid weight loss.

Dehydration, especially if vomiting or diarrhoea is severe.

Pancreatitis (inflammation of the pancreas) which is very rare but serious. Symptoms include severe, persistent abdominal pain that may spread to the back, with our without vomiting. If this occurs, stop taking the medication and seek urgent medical attention immediately.

Question 3

Accepted Answer

If you have been prescribed an injection:

Inject once a week on the same day each week, at a time that suits you.

You can inject into the abdomen (stomach) avoiding an area around the tummy button of about 5cm(2 inches), thigh, or upper arm. Rotate your injection site each week to help reduce skin irritation.

The medication can be taken with or without food.

If you miss a dose, follow the advice in the patient information leaflet or contact our clinical team for guidance.

Storage

Store unused pens in the refrigerator (2–8°C) unless otherwise stated in the manufacturer's instructions.

Do not freeze the medication. If it has been frozen, do not use it.

Once in use, some pens can be kept at room temperature for a limited period, depending on the brand. Always check the storage instructions provided with your medication.

Keep the pen cap on when not in use and store it away from direct sunlight and heat

If you have been prescribed tablets:

For the medication to be absorbed properly, it is important to take it correctly:

Take one tablet once a day at the same time each morning.

Take it after at least 8 hours of fasting (usually first thing after waking).

Swallow the tablet whole with no more than 120 mL (about one large sip) of plain water.

Do not eat, drink (other than water), or take any other medications for at least 30 minutes after taking the tablet.

After at least 30 minutes, you can eat breakfast and take your other medications as normal.

Taking the tablet with food, too much water, or other medications significantly reduces how much of the medicine your body absorbs, making it less effective.

Need help?

If you are unsure how to take your medication, have missed a dose, or have any questions about your treatment, please contact our clinical team. We are here to support you throughout your weight loss journey.

Question 4

Accepted Answer

If you are pregnant, planning to become pregnant, or breastfeeding, GLP-1 weight loss medications may not be suitable for you. Speak to a clinician before starting treatment or if your circumstances change.

Do not use GLP-1 weight loss medication during pregnancy. These medicines are not recommended during pregnancy as weight loss is not advised while pregnant and there is limited information about their safety in pregnancy.

If you are planning a pregnancy, speak to your healthcare team in advance. You may need to stop treatment before trying to conceive (the timing depends on the specific medication you are taking).

If you become pregnant while taking a GLP-1 medication, stop taking the medication and contact your clinician or healthcare provider for advice.

Breastfeeding: GLP-1 medications are generally not recommended while breastfeeding unless specifically advised by a healthcare professional.

Question 5

Accepted Answer

If you are able to become pregnant, you should use effective contraception while taking GLP-1 weight loss medication.

Some GLP-1 medications can affect how quickly food leaves the stomach, which may impact the absorption of some medicines taken by mouth.

If you use the oral contraceptive pill, speak to your clinician for advice, as additional contraceptive precautions may be recommended depending on the medication prescribed.

If you are starting or increasing the dose of certain GLP-1 medications, you may need to use an additional method of contraception for a short period.

Your clinician will discuss pregnancy, breastfeeding, and contraception with you before starting treatment to make sure the medication is safe and appropriate for your circumstances.

Question 6

Accepted Answer

If you are taking hormone replacement therapy (HRT), it is important to tell your clinician before starting GLP-1 weight loss medication.

GLP-1 medications slow down how quickly food leaves your stomach. This may affect how some medicines taken by mouth are absorbed, including some forms of HRT.

Continue taking your HRT as prescribed unless advised otherwise by your healthcare professional.

Tell your clinician if you take oral HRT tablets, as they may need to consider this when reviewing your treatment.

HRT patches, gels, sprays, and other non-oral forms are not expected to be affected in the same way, but you should still inform your clinician that you are using them.

If you notice any changes in your menopause symptoms after starting GLP-1 treatment, such as changes in hot flushes, sleep, or mood, speak to your healthcare team.

Your clinician will review all your current medications before prescribing GLP-1 treatment to ensure it is safe and suitable for you.

How the medications compare?

Important clinical information

Tirzepatide

Semaglutide

Semaglutide

How the medications compare?

Important clinical information

How the Medication Works

Side effects of medication

How to use? Important information

Pregnancy

Contraception

HRT and GLP-1 medication

Tirzepatide

Semaglutide

Semaglutide