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Exenatide for diabetes

Byetta, Bydureon

Exenatide is given as an injection just under the surface of the skin.

Store unopened packs of exenatide in a fridge. Once in use, a pack can be kept for up to 30 days at room temperature.

The most common side-effect is feeling sick (nausea) - this will reduce over time. If at any time you develop severe stomach pain and sickness (vomiting), speak with a doctor as soon as possible.

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About exenatide

Type of medicine

An antidiabetic injection

Used for

Type 2 diabetes mellitus in adults and children aged 10 years or older

Also called

Byetta® (standard-release exenatide); Bydureon® (prolonged-release exenatide)

Available as

Subcutaneous injection available in pre-filled 'pens'

Insulin is a hormone which is made naturally in your body, in 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 diabetes (diabetes mellitus).

People with 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 the food they eat but, for other people, medicines are given alongside the changes in diet. Exenatide is one of the medicines that are prescribed for people with type 2 diabetes.

Exenatide 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. Exenatide 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.

Exenatide is given as an injection just under the surface of the skin. It is administered using a syringe and needle or by using an injection device called a pre-filled pen. It is used in addition to other antidiabetic medicines. There are two types of exenatide injection available. There is a standard-release injection (brand name Byetta®) which is given twice daily, and there is a prolonged-release injection (brand name Bydureon®) which is given once a week.

Before using exenatide

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 using exenatide 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 ever had an inflamed pancreas (pancreatitis).

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

  • 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.

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

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How to use exenatide

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

  • If you are using Byetta®, you will be advised to inject two doses a day. You should have each injection within the 60-minute period before a main meal, and the two doses should be at least six hours apart. The best way to achieve this is to have your first injection during the hour before your first meal of the day, and the second injection during the hour before your evening meal.

  • If you forget to use exenatide before a meal, do not inject it after you have eaten, but instead just wait until your next dose is due.

  • If you are using Bydureon®, you will be advised to inject one dose a week, on the same day of 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. 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 your next scheduled dose is due within three days, miss out the forgotten dose and take your next dose when it is due.

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.

  • Each time you collect a prescription, check that you have been given the brand and strength of exenatide that you are expecting. If anything looks different from what you have had before, ask your pharmacist to check the prescription for you.

  • Make sure you know what it feels like if your blood sugar is low. This is known as hypoglycaemia, or a 'hypo'. Although exenatide is unlikely to cause low blood sugar, other medicines that you are taking for diabetes alongside it may. 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, jelly babies or a sugary drink (non-diet), and then follow this up with a snack such as a sandwich or a banana.

  • 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.

  • 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.

  • 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. Exenatide can interfere with the way some other medicines are absorbed. Because of this, some medicines should not be taken during the hour before exenatide is given, or during the four hours after it has been given.

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

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Can exenatide 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 exenatide. 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 exenatide side-effects (these affect more than 1 in 10 people)

What can I do if I experience this?

Feeling sick (nausea) or being sick (vomiting)

Stick to simple foods - avoid rich or spicy meals


Drink plenty of water to replace lost fluids.

Stick to simple foods - avoid rich or spicy meals

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

What can I do if I experience this?

Constipation, indigestion (acid reflux), wind (flatulence), bloating, stomach discomfort

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

Feeling dizzy or weak

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


Drink plenty of water and ask your pharmacist to recommend a suitable painkiller. If the headaches continue, let your doctor know

Lack of appetite, loss of weight, itching or skin rash, sweating, feeling jittery, injection site problems

Let your doctor or diabetes clinic know if any of these become troublesome

Important: medicines like exenatide can cause persistent and severe tummy (abdominal) pain with sickness (nausea and 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 the injections, speak with your doctor or pharmacist for further advice.

How to store exenatide

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

  • Exenatide can be kept for four weeks at room temperature as long as this is below 25°C and it is kept away from direct heat and sunlight. It is, however, best to store unopened packs in a refrigerator. Do not freeze exenatide.

  • Byetta® pens must be discarded 30 days after being first used.

  • Bydureon® pens are for single use only and should be discarded after first use.

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.

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