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GLP-1 Drugs subcutaneous solution (10 mcg/0.04 mL; 5 mcg/0.02 mL)

Exenatide

Generic name: exenatide (Byetta)

Brand names: Byetta Prefilled Pen

Last updated November 2, 2026 0 views
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What is Byetta?

This medication guide provides information about the Byetta brand of exenatide. Bydureon is another brand of exenatide that is not covered in this medication guide.

Exenatide is an injectable medicine for diabetes that helps control blood sugar levels. This medication helps your pancreas produce insulin more effectively. Byetta is a short-acting version of exenatide.

Byetta is used along with diet and exercise to improve blood sugar control in adults with type 2 diabetes. Byetta is not for treating type 1 diabetes.

Byetta may also be used for purposes not listed in this medication guide.

This section was rewritten for readability and reviewed for meaning.

Warnings

You should not use this medicine if you have severe kidney disease (or you are on dialysis), or if you have slowed digestion or diabetic ketoacidosis.

You should not use this medicine if exenatide has ever caused you to have low platelet levels in your blood.

Stop using this medicine and call your doctor immediately if you have nausea and vomiting with severe pain in your upper stomach that spreads to your back.

This section was rewritten for readability and reviewed for meaning.

Before taking this medicine

You should not use this medicine if you are allergic to exenatide (Bydureon or Byetta), or if you have:

  • severe kidney disease (or if you are on dialysis);
  • a severe stomach disorder that causes slow digestion;
  • a history of low levels of platelets (blood cells that help your blood to clot) while using exenatide; or
  • diabetic ketoacidosis (call your doctor for treatment with insulin).

Tell your doctor if you have ever had:

  • kidney disease or a history of kidney transplant;
  • a stomach disorder that causes slow digestion;
  • pancreatitis; or
  • gall stones.

Follow your doctor's instructions about using this medicine if you are pregnant or you become pregnant. Controlling diabetes is very important during pregnancy, and having high blood sugar may cause complications for both the mother and the baby.

Byetta can make birth control pills less effective. If you take birth control pills, take your pill at least 1 hour before your Byetta injection.

It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk.

Exenatide is not approved for use by anyone younger than 18 years old.

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Byetta side effects

Get emergency medical help if you have signs of an allergic reaction: hives, itching; rapid heartbeats; difficulty breathing; feeling light-headed; swelling of your face, lips, tongue, or throat.

Some people using exenatide have had serious or fatal bleeding due to low levels of platelets (blood cells that help your blood to clot). Stop using Byetta and call your doctor right away if you have unusual bleeding or bruising.

This medicine may cause serious side effects. Stop using this medicine and call your doctor immediately if you have:

  • pancreas or gallbladder problems--pain in your upper stomach spreading to your back, nausea and vomiting, fever, fast heart rate, yellowing of your skin or eyes;
  • low blood sugar--headache, hunger, sweating, irritability, dizziness, nausea, fast heart rate, and feeling anxious or shaky; or
  • kidney problems--little or no urination, painful or difficult urination, swelling in your feet or ankles, feeling tired or short of breath.

Common side effects of exenatide may include:

  • indigestion, nausea, vomiting;
  • diarrhea, constipation; or
  • itching or a small bump where the medicine was injected.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

This section was rewritten for readability and reviewed for meaning.

How should I use Byetta?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Byetta is injected under the skin. A healthcare provider may teach you how to properly use the medication by yourself.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you don't understand all instructions.

Prepare your injection only when you are ready to give it. You must give the injection right away after mixing.

Byetta is usually injected twice a day, before the morning and evening meals. Do not use after eating a meal. You must use Byetta within 60 minutes (1 hour) before eating. Your Byetta doses should be given at least 6 hours apart.

You may have low blood sugar (hypoglycemia) and feel very hungry, dizzy, irritable, confused, anxious, or shaky. To quickly treat hypoglycemia, eat or drink a fast-acting source of sugar (fruit juice, hard candy, crackers, raisins, or non-diet soda).

Your doctor may prescribe a glucagon injection kit in case you have severe hypoglycemia. Be sure your family or close friends know how to give you this injection in an emergency.

Also watch for signs of high blood sugar (hyperglycemia) such as increased thirst or urination.

Blood sugar levels can be affected by stress, illness, surgery, exercise, alcohol use, or skipping meals. Ask your doctor before changing your dose or medication schedule.

Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

Never share an injection pen or syringe with another person, even if the needle has been changed. Sharing these devices can allow infections or disease to pass from one person to another.

Byetta can lower your platelet counts for up to 10 weeks after you stop using this medicine. You may need frequent medical tests while using this medicine and for a short time after you stop.

Byetta is only part of a complete treatment program that may also include diet, exercise, weight control, regular blood sugar testing, and special medical care. Follow your doctor's instructions very closely.

Storing unopened (not in use) Byetta: Keep the medicine in its original container. Refrigerate and use until expiration date. Protect from light.

Do not freeze Byetta, and throw away the medicine if it has been frozen.

Storing opened (in use) Byetta: Store at room temperature and use within 30 days. Protect from heat and bright light. Do not store the injection pen with a needle attached.

What happens if I miss a dose?

Skip the missed dose and take your next dose at the usual time. Do not take two doses at once.

This section was rewritten for readability and reviewed for meaning.

What happens if I overdose?

Seek emergency medical help or call the Poison Help line at 1-800-222-1222.

Taking too much can lead to severe nausea and vomiting, or signs of low blood sugar such as headache, hunger, irritability, dizziness, or feeling shaky.

You should not mix Byetta with insulin in the same syringe. Do not use Byetta together with Bydureon.

Avoid drinking alcohol. It can lower your blood sugar.

This section was rewritten for readability and reviewed for meaning.

What other drugs will affect Byetta?

If you take the following medicines, make sure to take them at least 1 hour before you use Byetta:

  • an antibiotic; or
  • birth control pills.

If you take these medicines with food, have them with a meal or snack that is separate from the times you use Byetta.

Exenatide can make it harder for your body to absorb other medicines you take by mouth. Inform your doctor about all your current medicines and any new ones you start or stop using, especially:

  • blood pressure medicine;
  • a diuretic or "water pill";
  • insulin or oral diabetes medicine;
  • pain medicine;
  • lovastatin (Advicor, Altoprev, Mevacor); or
  • warfarin (Coumadin, Jantoven).

This list is not complete. Other drugs may affect Byetta, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

This section was rewritten for readability and reviewed for meaning.

Common questions about exenatide

Which GLP-1 drug is best for weight loss?
The most effective GLP-1 drug for weight loss currently (as of early 2026) is tirzepatide, marketed under the names Zepbound (for weight loss) and Mounjaro (for diabetes). Clinical trials and recent meta-analyses consistently show tirzepatide delivers the most substantial weight reduction among GLP-1 medications, with average losses of up to 22.5% of body weight. Continue reading
How long can Bydureon be unrefrigerated?
Bydureon can be left unrefrigerated at room temperature for up to 4 weeks (28 days) as long as the temperature in the room does not exceed 86°F (30°C). This will allow you to take your weekly dose with you, especially if you are traveling. Never leave your Bydureon pen in the sun or a hot place, like your car's jockey box, because it will become too hot. And do not put it back in the refrigerator if it has been out of the refrigerator for longer than an hour. Continue reading
How do you use the Bydureon pen?
The Bydureon pen was discontinued in March 2021 and has been replaced by Bydureon Bcise Autoinjector. The Bydureon Bcise Autoinjector has been designed to be easy to use. There is no need to attach a needle (the hidden needle is already attached) or turn a dial. Always store your Bydureon Bcise autoinjector flat in the refrigerator. It can be self-injected at home once a week and it is easy to learn how to administer it yourself. If you have difficulty injecting it, a family member, friend, caregiver, or healthcare provider may be able to do it for you. Instructions for injecting the Bydureon Bcise autoinjector are given below. Continue reading
How long does it take for Bydureon Bcise to take effect?
Bydureon Bcise starts working as soon as you inject the first dose but it may take two or more weeks before it has a noticeable effect on your blood sugar, and longer before it decreases your HbA1c levels. Bydureon Bcise builds up gradually in your body with each weekly dose and reaches its optimal level after 10 weeks of dosing. The extended-release delivery system keeps a consistent level of medicine in your body. Continue reading
How do you use the Bydureon Bcise autoinjector?
The Bydureon Bcise Autoinjector has been designed to be easy to use. There is no need to attach a needle (the hidden needle is already attached) or turn a dial. Always store your Bydureon Bcise autoinjector flat in the refrigerator. Continue reading

Related medicines

Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
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