Skip to main content

Semaglutide

Ozempic, Rybelsus

Semaglutide can be taken orally as a tablet or given as an injection using a pre-filled pen. Your doctor will discuss with you which type of medicine might be most suitable for you.

Semaglutide injections should be given once each week on the same day each week. Store unopened packs of semaglutide in a fridge. Once in use, you can keep the pre-filled pen at room temperature.

Semaglutide tablets should be taken once every day at least two hours after food. You should not eat, drink or take any other oral medication for at least 30 minutes after your dose.

The most common side-effects are feeling sick (nausea) and diarrhoea - these usually reduce over time. If at any time you develop severe stomach pain with sickness (nausea and vomiting), speak with a doctor as soon as possible.

Continue reading below

About semaglutide

Type of medicine

A GLP-1 analogue

Used for

Treatment of type 2 diabetes mellitus

Also called

Ozempic®, Rybelsus®

Available as

Tablets and injections in pre-filled pens

Insulin is a hormone which is made naturally in your body, by the pancreas. It helps to control the levels of sugar (glucose) in your blood. If your body does not make enough insulin, or if it does not use the insulin it makes effectively, this results in the condition called type 2 diabetes (diabetes mellitus).

People with type 2 diabetes need treatment to control the amount of sugar in their blood. This is because good control of blood sugar levels reduces the risk of complications later on. Some people can control the sugar in their blood by making changes to their diet and lifestyle but, for other people, medicines are given alongside the changes in diet. Semaglutide is one of the medicines that are prescribed for people with type 2 diabetes.

Semaglutide very closely resembles a natural hormone called glucagon-like peptide-1 (GLP-1) and it works in three ways. It increases the amount of insulin produced by your body, which then reduces the level of sugar in your blood.

It also reduces the amount of a substance called glucagon being produced by your pancreas. Glucagon causes your liver to produce more sugar, so by reducing the amount of glucagon in your body, this also helps to reduce the levels of sugar in your blood. Semaglutide also works on your stomach so that food passes more slowly through it. This means that the sugar from your meals takes longer to get into your blood.

Semaglutide can be used on its own or in addition to other diabetes medicines. It can be taken orally as a tablet or given as an injection just under the surface of the skin. An injection device called a pre-filled pen is used to inject a dose once weekly. Tablets must be taken every day.

Before starting semaglutide treatment

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start treatment with semaglutide it is important that your doctor knows:

  • If you are pregnant, trying for a baby, or breastfeeding.

  • If you have a problem with your stomach or digestive system.

  • If you have any problems with the way your liver works or the way your kidneys work.

  • If you have an underactive or overactive thyroid gland.

  • If you have ever had an inflamed pancreas (pancreatitis).

  • If you have ever had an allergic reaction to a medicine.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

Continue reading below

How to use semaglutide injections (Ozempic®)

  • Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack as well as any information you are given by your doctor or diabetes clinic. The manufacturer's leaflet will provide you with a full list of the side-effects which you may experience.

  • Use Ozempic® exactly as your doctor tells you to. Your doctor or diabetes nurse will show you how to inject yourself. Ozempic® should be injected into the skin on your upper arms, thigh, or tummy (abdomen). Try to choose a different injection site for each of your injections.This will help to prevent skin problems and difficulties in injecting.

  • After each injection remove the needle to help prevent problems with blockage, leakage or infection.

  • Ozempic® should be injected once each week, on the same day each week. Each pre-filled pen provides a single dose. The injection can be given at any time of the day, and it can be given either before or after a meal. It is best to have your dose around the same time each day.

  • There are three different strengths of semaglutide injection. You will start with a 0.25 mg dose once a week for four weeks, followed by 0.5 mg once a week for at least another four weeks. Depending on how well your blood sugar is controlled at this dose, your doctor may ask you to increase the dose to 1 mg weekly.

  • If you forget to use the injection on your usual day, use it as soon as you remember and keep to your normal weekly schedule. However, if it has been more than five days since the missed dose, skip the forgotten dose and take your next dose when it is due.

  • You can change the day of your scheduled dose as long as you leave at least three days (72 hours) between doses. For example, if your dose is usually scheduled for Monday morning you could change it to Thursday morning at the earliest. Then continue each week on Thursdays.

How to take semaglutide tablets (Rybelsus®)

  • Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The manufacturer's leaflet will give you more information about semaglutide tablets and a full list of side-effects which you may experience from taking them.

  • Take semaglutide tablets exactly as your doctor tells you to. There are three strengths of semaglutide tablet. The starting dose is one 3 mg tablet taken each day for one month followed by one 7 mg tablet each day for at least another month. Depending on how well your blood sugar is controlled at this dose your doctor may ask you to increase the dose to one 14 mg tablet taken each day.

  • It is best to take your dose around the same time each day.

  • Swallow the tablet whole with a small drink of water. The tablet should be taken on an empty stomach at least two hours after food. You should not eat or drink or take any other oral medication for at least 30 minutes after taking semaglutide tablets.

  • If you forget to take a dose, leave out the forgotten dose and take the next dose when it is due the following day. Do not take two doses together to make up for a missed dose.

Continue reading below

Getting the most from your treatment

  • It is important that you keep your regular doctor's and clinic appointments. This is so that your progress can be monitored. You will need regular check-ups with an eye clinic and a foot clinic as well as with your doctor and diabetes clinic.

  • Your doctor may recommend that you test for sugar (glucose) in your blood or urine regularly to check that your diabetes is being controlled. Your doctor or diabetes nurse will show you how to do this.

  • If you have been given advice by your doctor about changes to your diet, stopping smoking or taking regular exercise, it is important for you to follow the advice you have been given.

  • Make sure you know what it feels like if your blood sugar is low. This is known as hypoglycaemia, or a 'hypo'. Although semaglutide is unlikely to cause low blood sugar by itself, other diabetes medicines that you are taking may do so.

  • The first signs of hypoglycaemia are feeling shaky or anxious, sweating, looking pale, feeling hungry, having a feeling that your heart is pounding (palpitations), and feeling dizzy. If this happens, eat something containing sugar, such as dextrose tablets, sweets/candies or a sugary drink (non-diet), and then follow this up with a snack such as a sandwich or a piece of fruit.

  • If you are a driver you should take special care, as your ability to concentrate may be affected if your diabetes is not well controlled. You may be advised to check your blood sugar levels before you travel and to have a snack with you on long journeys.

  • Do not drink alcohol, as it can affect the control of your blood sugar. Ask your doctor if you need further advice about this.

  • It is important not to become dehydrated whilst being treated with semaglutide. Make sure you drink the recommended amount of fluids each day.

  • If you get unusually thirsty, pass urine more frequently than normal, or feel very tired, you should let your doctor know. These are signs that there is too much sugar in your blood and your treatment may need adjusting.

  • Check with your doctor before taking up any new physical exercise, as this will have an effect on your blood sugar levels and you may need to check your blood or urine levels more regularly.

  • You should avoid becoming pregnant whilst being treated with semaglutide. Your doctor can advise you on suitable forms of contraception for you and your partner.

  • If you are due to have an operation or dental treatment, you should tell the person carrying out the treatment that you have diabetes and give them a list of the medicines you are taking.

  • If you buy any medicines, always check with a pharmacist that they are suitable for you to take.

  • Treatment for diabetes is usually lifelong. Continue with semaglutide unless you are told otherwise by your doctor.

Can semaglutide cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with semaglutide. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

Very common semaglutide side-effects (these affect more than 1 in 10 people)

What can I do if I experience this?

Nausea (feeling sick)

Stick to simple foods - avoid rich or spicy meals

Diarrhoea

Drink plenty of water to replace lost fluids

Low blood sugar (hypoglycaemia) when used with insulin, gliclazide, glimepiride, glipizide or tolbutamide. Signs include feeling shaky or anxious, sweating, looking pale, feeling hungry, a feeling that your heart is pounding (palpitations), and feeling dizzy

Eat or drink something sugary and then follow this up with a snack such as a sandwich or a piece of fruit

Common semaglutide side-effects (these affect fewer than 1 in 10 people)

What can I do if I experience this?

Constipation

Drink plenty of water and eat a balanced diet including lots of fruit and vegetablets

Being sick (vomiting)

Stick to simple foods - avoid rich or spicy meals. Drink plenty of water to replace lost fluids

Indigestion, bloating, wind, tummy (abdominal) pain

Stick to simple foods - avoid rich or spicy meals

Tiredness, decreased appetite and weight, increased heart rate

Let your doctor know if these become troublesome

Worsening of existing diabetes-related vision problems

Attend routine eye examinations and let your doctor know if you notice any problems with your eyes or vision

Feeling dizzy (when being treated with semaglutide injections)

Do not drive and do not use tools or machines until you feel better

Important: medicines like semaglutide can cause persistent and severe tummy (abdominal) pain with sickness (nausea and/or vomiting) in a few people. If this happens to you, you should speak with your doctor as soon as possible as these can be symptoms of an inflamed pancreas (pancreatitis).

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

How to store semaglutide

  • Keep all medicines out of the reach and sight of children.

  • Store unopened packs of pre-filled pens in a fridge. Do not freeze the pens and do not use them if you think they have been accidentally frozen.

  • Once in use you can keep the pre-filled pen at room temperature for up to six weeks. Keep the cap on the pen to protect the medicine from light.

  • Store the tablets in their original packaging in a cool, dry place, away from direct heat and light.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

flu eligibility checker

Are you protected against flu?

See if you are eligible for a free NHS flu jab today.

symptom checker

Feeling unwell?

Assess your symptoms online for free