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Generic name: exenatide

What is Byetta?

  • Byetta is an injectable prescription medicine that may improve blood sugar (glucose) control in adults with type 2 diabetes mellitus, when used with a diet and exercise program.
  • Byetta is not insulin.
  • Byetta is not a substitute for insulin.
  • The use of Byetta with short acting insulin is not recommended.
  • The use of Byetta with rapid acting insulin is not recommended.
  • Byetta is not for people with type 1 diabetes or people with diabetic ketoacidosis.
  • It is not known if Byetta can be used in people who have had pancreatitis.
  • It is not known if Byetta is safe and effective in children.
  • Byetta should not be used in people who have severe kidney problems.

What is the most important information I should know about Byetta?

  • Do not share your Byetta Pen with other people, even if the needle has been changed. You may give other people a serious infection or get a serious infection from them.
  • Serious side effects can happen in people who take Byetta, including inflammation of the pancreas (pancreatitis) which may be severe and lead to death. Stop using Byetta and call your healthcare provider right away if you have severe pain in your stomach area (abdomen) that will not go away, with or without vomiting. You may feel the pain from your abdomen to your back. These may be symptoms of pancreatitis.

Who should not take Byetta?

Do not use Byetta if:

  • you have had an allergic reaction to exenatide or any of the other ingredients in Byetta. See the end of this Medication Guide for a complete list of ingredients in Byetta.

Symptoms of a severe allergic reaction with Byetta may include:

  • swelling of your face, lips, tongue, or throat
  • problems breathing or swallowing
  • severe rash or itching
  • fainting or feeling dizzy
  • very rapid heartbeat

What should I tell my healthcare provider before taking Byetta?

Before taking Byetta, tell your healthcare provider about all of your medical conditions, including if you:

  • have or have had problems with your pancreas.
  • have severe problems with your stomach, such as delayed emptying of your stomach (gastroparesis) or problems with digesting food.
  • have or have had kidney problems, or have had a kidney transplant.
  • are pregnant or plan to become pregnant. It is not known if Byetta will harm your unborn baby. Tell your healthcare provider if you become pregnant while taking Byetta. Talk to your healthcare provider about the best way to control your blood sugar if you plan to become pregnant or while you are pregnant.
  • are breastfeeding or plan to breastfeed. It is not known if Byetta passes into your breast milk. You should talk with your healthcare provider about the best way to feed your baby while taking Byetta.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Byetta may affect the way some medicines work and some other medicines may affect the way Byetta works.

Especially tell your healthcare provider if you take:

  • other anti-diabetes medicines, especially sulfonylurea medicines or insulin.
  • birth control pills that are taken by mouth (oral contraceptives). Byetta may lower the amount of the medicine in your blood from your birth control pills and they may not work as well to prevent pregnancy. Take your birth control pills at least one hour before your injection of Byetta. If you must take your birth control pills with food, take it with a meal or snack at a time when you do not also take Byetta.
  • an antibiotic. Take antibiotic medicines at least one hour before taking Byetta. If you must take your antibiotic with food, take it with a meal or snack at a time when you do not also take Byetta.
  • warfarin sodium (Coumadin, Jantoven).
  • a blood pressure medicine.
  • a water pill (diuretic).
  • a pain medicine.
  • lovastatin (Altoprev, Mevacor, Advicor).

How should I take Byetta?

See the Pen User Manual that comes with Byetta for instructions for using the Byetta Pen and injecting Byetta.

  • Your healthcare provider may prescribe Byetta alone or with certain other medicines to help control your blood sugar.
  • Use Byetta exactly as your healthcare provider tells you to.
  • Your healthcare provider should teach you how to inject Byetta before you use it for the first time. Inject your dose of Byetta under the skin (subcutaneous injection) of your upper leg (thigh), stomach area (abdomen), or upper arm as instructed by your healthcare provider. Do not inject into a vein or muscle.
  • Do not mix Byetta and insulin in the same syringe or vial even if you take them at the same time.
  • Byetta is injected two times each day, at any time within 60 minutes (1 hour) before your morning and evening meals (or before the two main meals of the day, approximately 6 hours or more apart). Do not take Byetta after your meal.
  • If you miss a dose of Byetta, skip that dose and take your next dose at the next prescribed time. Do not take an extra dose or increase the amount of your next dose to make up for a missed dose.
  • If you use too much Byetta, call your healthcare provider. Too much Byetta can cause your blood sugar to drop quickly and you may have symptoms of low blood sugar. You may need medical treatment right away. Too much Byetta can also cause severe nausea and vomiting.
  • Follow your healthcare provider's instructions for diet, exercise, and how often to test your blood sugar. If you see your blood sugar increasing during treatment with Byetta, talk to your healthcare provider because you may need to adjust your current treatment plan for your diabetes.
  • Talk to your healthcare provider about how to manage high blood sugar (hyperglycemia) and low blood sugar (hypoglycemia), and how to recognize problems that can happen with your diabetes.

What are the possible side effects of Byetta?

Byetta may cause serious side effects, including:

Low blood sugar (hypoglycemia). Your risk for getting low blood sugar is higher if you take Byetta with another medicine that can cause low blood sugar, such as a sulfonylurea or insulin. The dose of your sulfonylurea or insulin medicine may need to be lowered while you use Byetta. Signs and symptoms of low blood sugar may include:

  • headache
  • drowsiness
  • weakness
  • hunger
  • fast heart beat
  • dizziness
  • confusion
  • anxiety, irritability or mood change
  • sweating
  • feeling jittery
  • blurred vision
  • slurred speech

Talk with your healthcare provider about how to treat low blood sugar.

  • Kidney problems. Byetta may cause new or worse problems with kidney function, including kidney failure.
    Dialysis or kidney transplant may be needed.
    • While taking Byetta: Call your healthcare provider right away if you have nausea, vomiting, or diarrhea that will not go away, or if you cannot take liquids by mouth. You may be at increased risk for kidney problems.
  • Stomach problems. Other medicines like Byetta may cause severe stomach problems. It is not known if Byetta causes stomach problems or will cause your stomach problems to worsen.
  • Severe allergic reactions. Severe allergic reactions can happen with Byetta. Stop taking Byetta and get medical help right away if you have any symptom of a severe allergic reaction. See "Who should not use Byetta?"

The most common side effects of Byetta include:

  • nausea
  • vomiting
  • diarrhea
  • feeling jittery
  • dizziness
  • headache
  • indigestion
  • constipation
  • weakness

Nausea is most common when you first start using Byetta but may decrease over time.

Talk to your healthcare provider about any side effect that bothers you or that does not go away. These are not all the possible side effects of Byetta.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

General information about the safe and effective use of Byetta

Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use Byetta for a condition for which it was not prescribed. Do not give Byetta to other people, even if they have the same symptoms that you have. It may harm them. You can ask your healthcare provider or pharmacist for information about Byetta that is written for health professionals.

How should I store Byetta?

  • Store your new, unused Byetta Pen in the original carton in a refrigerator at 36°F to 46°F (2°C to 8°C).
  • After first use, keep your Byetta Pen at a temperature cooler than 77°F (25°C).
  • Do not freeze your Byetta Pen. Do not use Byetta if it has been frozen.
  • Protect Byetta from light.
  • Use a Byetta Pen for only 30 days. Throw away a used Byetta Pen after 30 days, even if there is some medicine left in the pen.
  • Do not use Byetta after the expiration date printed on the label.

Keep your Byetta Pen, pen needles, and all medicines out of the reach of children.

What are the ingredients in Byetta?

Active ingredient: exenatide

Inactive ingredients: metacresol, mannitol, glacial acetic acid, and sodium acetate trihydrate in water for injection.

For more information call 1-877-700-7365.

Source: National Library of Medicine. Last updated January 31, 2019.