Byetta is a brand-name prescription medication. It’s used with a diet and exercise program to help lower blood sugar levels (glucose) in adults with type 2 diabetes. Byetta is not currently approved for use in children.

Byetta contains exenatide, which is a type of drug known as a glucagon-like peptide-1 (GLP-1) agonist. Byetta is given by injection.

Byetta comes in a prefilled injection pen. You use the pen to give yourself an injection under your skin (a subcutaneous injection). You inject your dose before each of your two main meals of the day (such as breakfast and dinner).

If you take Byetta, you may also be prescribed other medications such as metformin, a sulfonylurea, or both to help lower your blood sugar levels.

Effectiveness

Byetta is effective when used on its own and when used with various combinations of diabetes drugs. It significantly lowers your hemoglobin A1c (HbA1c), which measures your average blood sugar levels over the past three months.

In one clinical study of Byetta used on its own, people receiving Byetta had a reduction in their average HbA1c levels of 0.7%–0.9% after 24 weeks. This was compared to a 0.2% reduction in people receiving a placebo (a treatment without an active drug). People receiving Byetta also had their average fasting blood sugar reduced by 17–19 mg/dL, compared with 5 mg/dL in people receiving a placebo.

Similar results were seen in other clinical studies where people received Byetta with other antidiabetic medications. These medications include metformin, a sulfonylurea (such as glipizide), a thiazolidinedione (such as pioglitazone), and insulin glargine.

Byetta is available only as a brand-name medication. It’s not currently available in generic form.

Byetta contains one active drug ingredient: exenatide. Exenatide is also available in extended-release form as the brand-name drug Bydureon.

The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Drug forms and strengths

Byetta comes as a prefilled injection pen. It’s available in two strengths: 5 mcg per dose and 10 mcg per dose. Each pen contains 60 doses.

Dosage for type 2 diabetes

Your starting dosage of Byetta will likely be 5 mcg injected twice a day, in the hour before each of your two main meals. Most people give themselves one injection in the hour before breakfast and another in the hour before dinner.

However, if you don’t eat much breakfast, you could choose to have your first injection in the hour before lunch. Your second injection would still be in the hour before your dinner, as long as these meals are at least six hours apart. Ask your doctor for advice if you’re not sure when to give yourself your injections.

After four weeks, your doctor may increase your dosage to 10 mcg twice a day. This will depend on how well your blood sugar levels respond to Byetta injections. Your doctor will decide what the best dosage is for you.

What if I miss a dose?

If you forget to have your injection before a meal, don’t have it after the meal. Just leave out the missed dose and have your next injection as usual when it’s time. Never use a double dose to make up for a missed dose.

Medication reminders can help make sure you don’t miss a dose.

Will I need to use this drug long term?

Byetta is meant to be used as a long-term treatment. If you and your doctor determine that Byetta is safe and effective for you, you’ll likely take it long term.

Byetta can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking Byetta. These lists do not include all possible side effects.

For more information on the possible side effects of Byetta, talk with your doctor or pharmacist. They can give you tips on how to deal with any side effects that may be bothersome.

More common side effects

The more common side effects of Byetta can include:

  • nausea
  • vomiting
  • diarrhea
  • indigestion
  • constipation
  • dizziness
  • feeling jittery
  • headaches
  • reduced appetite
  • hypoglycemia (low blood sugar; see “Side effect details” below to learn more)

Most of these side effects may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk with your doctor or pharmacist.

Serious side effects

Serious side effects from Byetta aren’t common, but they can occur. Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency.

Serious side effects can include:

  • Acute pancreatitis (inflammation of the pancreas). Symptoms can include:
    • severe pain in your abdomen (belly) that won’t go away
    • pain in your back
    • nausea
    • vomiting
  • Problems with kidney function, including kidney failure. Symptoms can include:
    • urinating less than usual
    • swollen ankles or feet
    • confusion
    • fatigue (lack of energy)
  • Severe allergic reaction. See “Side effect details” below.

Side effect details

You may wonder how often certain side effects occur with this drug, or whether certain side effects pertain to it. Here’s some detail on some of the side effects this drug may or may not cause.

Allergic reaction

As with most drugs, some people can have an allergic reaction after taking Byetta. Symptoms of a mild allergic reaction can include:

  • skin rash
  • itchiness
  • flushing (warmth and redness in your skin)

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include:

  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your tongue, mouth, or throat
  • trouble breathing
  • chest tightness

Call your doctor right away if you have a severe allergic reaction to Byetta. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency.

Allergic reactions to Byetta weren’t reported in clinical studies. However, mild and severe allergic reactions have been reported since the drug came on the market in 2005. It’s not clear how often allergic reactions occur.

Hypoglycemia

Your blood sugar levels may fall too low while you’re taking Byetta. This is called hypoglycemia. It’s more likely to happen if you’re using Byetta with other drugs to lower your blood sugar, especially insulin and sulfonylurea drugs such as gliclazide.

  • In a 24-week clinical study of Byetta used on its own, hypoglycemia occurred in 5.2% of people using 5 mcg of Byetta twice a day. In comparison, hypoglycemia occurred in 1.3% of people using a placebo (a treatment without an active drug).
  • In a 30-week clinical study of Byetta used with metformin (which helps lower blood sugar), hypoglycemia occurred in 4.5% of people using 5 mcg of Byetta twice a day. Hypoglycemia occurred in 5.3% of people using placebo.
  • In a 30-week clinical study of Byetta used with a sulfonylurea (which helps lower blood sugar), hypoglycemia occurred in 14.4% of people using 5 mcg of Byetta twice a day. In comparison, hypoglycemia occurred in 3.3% of people using placebo.

Talk to your doctor about what to do if you experience symptoms of hypoglycemia, which can include:

  • fast heartbeat
  • sweating
  • pale skin
  • feeling weak or tired
  • feeling jittery or shaky
  • dizziness
  • hunger
  • headache
  • blurred vision
  • anxiety
  • confusion
  • trouble concentrating
  • sudden mood changes

Pancreatitis

Pancreatitis was not reported in clinical studies of Byetta. However, a few people using Byetta have experienced acute pancreatitis (inflammation of the pancreas) since the drug came on the market in 2005. Some of these cases were serious or fatal. The exact risk of this side effect is unknown because it’s not known exactly how many people have taken Byetta during this time.

Call your doctor right away if you experience any symptoms of acute pancreatitis. Your doctor may tell you to stop using Byetta. Symptoms of acute pancreatitis can include:

  • severe pain in your abdomen (belly) that may spread to your back and won’t go away
  • nausea
  • vomiting
  • bloated or swollen belly
  • fever

Weight loss or weight gain

It’s unlikely that you’ll gain weight while taking Byetta, but you might lose weight.

  • In a 24-week clinical study, people using Byetta on its own lost an average of 6–6.4 lbs. (2.7–2.9 kg). People receiving a placebo lost an average of 3.3 lbs. (1.5 kg) over the same time period.
  • In a 30-week clinical study, people using Byetta with metformin lost an average of 2.9–5.7 lbs. (1.3–2.6 kg). People receiving a placebo lost an average of 0.4 lbs. (0.2 kg) over the same time period.
  • In a 30-week clinical study, people using Byetta with a sulfonylurea lost an average of 2.4–3.5 lbs. (1.1–1.6 kg). People receiving a placebo lost an average of 1.8 lbs. (0.8 kg) over the same time period.

The weight loss side effect can be beneficial for people with type 2 diabetes. Weight loss is most likely caused by Byetta making you want to eat less. In clinical studies, reduced appetite was reported by 1%–2% of people treated with Byetta. However, Byetta is not a weight loss drug and should not be used solely for this purpose.

Weight gain was not reported with Byetta in these studies. Talk to your doctor if you’re concerned about gaining weight while using Byetta.

Diarrhea

Some people using Byetta experience diarrhea. In clinical studies, diarrhea was reported in 1%–2% of people using Byetta on its own. It was reported in 13% of people using Byetta with metformin, a sulfonylurea, or both.

If you get diarrhea while using Byetta, talk with your doctor or pharmacist about how to manage it. Drink plenty of fluids to avoid getting dehydrated (when your body loses more fluid than you drink). See your doctor if you experience diarrhea that is severe or doesn’t go away.

Nausea

You may find that you feel nauseated when you first start using Byetta. This is why you’ll start treatment with a low dose.

  • In clinical studies, 8% of people using Byetta on its own experienced nausea and 4% experienced vomiting. In comparison, no one who received a placebo experienced nausea and vomiting.
  • In clinical studies, 44% of people using Byetta plus metformin, a sulfonylurea, or both experienced nausea and 13% experienced vomiting. Of people receiving a placebo, 18% experienced nausea and 4% experienced vomiting.

Feelings of nausea tend to get better with time. Talk with your doctor if you’re still feeling nauseous after a few weeks.

While you’re using Byetta, it’s important to tell your doctor right away if you suddenly start getting new feelings of nausea along with severe stomach pain or vomiting. These could be symptoms of acute pancreatitis (see the “Pancreatitis” section above).

Hair loss

Hair loss (alopecia) was not reported in clinical studies of Byetta. However, it has been reported by some people using Byetta since the drug was approved.

Talk with your doctor if you’re concerned about hair loss while using Byetta.

Pancreatic cancer

A literature review of safety issues with Byetta and other drugs in the same class did not find any association between pancreatic cancer and use of these drugs. Talk to your doctor if you’re concerned about your risk of pancreatic cancer.

Thyroid cancer

Byetta hasn’t been shown to cause thyroid cancer and doesn’t have a boxed warning for thyroid cancer. However, the long-acting form of exenatide, which is the main drug in Byetta, does have such a warning. This form of exenatide is available as the brand-name drug Bydureon.

An FDA boxed warning is used to alert doctors and patients about potentially serious side effects that might be associated with a drug. Bydureon has one because it was shown to cause thyroid cancer in some animals. However, results from animal studies do not necessarily apply to humans.

The FDA has also issued boxed warnings about thyroid cancer for other medications in the same drug class as Byetta. These drugs are liraglutide (Victoza), semaglutide (Ozempic), albiglutide (Tanzeum), and dulaglutide (Trulicity). These warnings are also based on animal studies. However, these drugs have not been shown to cause thyroid cancer in humans.

It’s hard to prove whether a drug or class of drugs can increase the risk for developing any kind of cancer. This is because data needs to be collected over a very long period of time. Much more evidence is needed before experts can say with certainty if these drugs do or don’t increase the risk of thyroid cancer.

It’s worth noting that thyroid cancer is a relatively uncommon type of cancer. Talk with your doctor if you’re concerned about your risk of thyroid cancer.

As with all medications, the cost of Byetta can vary. To find current prices for Byetta in your area, check out GoodRx.com:

The cost you find on GoodRx.com is what you may pay without insurance. The actual price you’ll pay depends on your insurance plan, your location, and the pharmacy you use.

Financial and insurance assistance

If you need financial support to pay for Byetta, or if you need help understanding your insurance coverage, help is available.

AstraZeneca, the manufacturer of Byetta, offers a savings card called MySavingsRx, which can help lower the cost of Byetta. For more information and to find out if you’re eligible for support, call 844-631-3978 or visit the program website.

If you’d like to talk to someone who can help you better understand your insurance plan, you can talk with a Byetta Prescription Coverage Counselor. To learn more, call 800-236-9933 or visit the program website.

Other drugs are available for treating type 2 diabetes. Some may be a better fit for you than others. If you’re interested in finding an alternative to Byetta, talk with your doctor. They can tell you about other medications that may work well for you.

Examples of other drugs that may be used to treat type 2 diabetes include:

  • metformin (Glucophage, Fortamet, Glumetza, Riomet)
  • sulfonylureas such as:
    • glimepiride (Amaryl)
    • glipizide (Glucotrol)
    • glyburide (DiaBeta, Glynase)
  • other GLP agonists (incretin mimetics) such as:
    • dulaglutide (Trulicity)
    • exenatide long-acting (Bydureon)
    • liraglutide (Victoza)
    • lixisenatide (Adlyxin)
    • semaglutide (Ozempic)
  • thiazolidinediones such as:
    • pioglitazone (Actos)
    • rosiglitazone (Avandia)
  • sodium-glucose co-transporter 2 (SGLT2) inhibitors such as:
    • canagliflozin (Invokana)
    • dapagliflozin (Farxiga)
    • empagliflozin (Jardiance)
    • ertugliflozin (Steglatro)
  • dipeptidyl peptidase-4 (DPP-4) inhibitors such as:
    • alogliptin (Nesina)
    • linagliptin (Tradjenta)
    • saxagliptin (Onglyza)
    • sitagliptin (Januvia)
  • insulin such as:
    • insulin glargine (Lantus, Toujeo)
    • insulin detemir (Levemir)

You may wonder how Byetta compares to other medications that are prescribed for similar uses. Here we look at how Byetta and Bydureon are alike and different.

Uses

Byetta and Bydureon are both FDA-approved to help control blood sugar levels in adults with type 2 diabetes. They are used along with a diet and exercise program.

Both of these medications contain exenatide, so they work the same way in the body. Byetta is a short-acting form of the drug that wears off after a few hours. Bydureon is a long-acting form of exenatide that works for a longer period. That means you don’t need to take Bydureon as often as Byetta.

Drug forms and administration

Byetta comes as a prefilled multidose injection pen. You give yourself an injection under your skin (subcutaneously) twice a day, before your main meals.

Bydureon comes as a single-dose injection pen or a single-dose syringe. It also comes as a single-dose prefilled autoinjector called Bydureon BCise. With all forms of Bydureon, you give yourself an injection under your skin once a week, on the same day each week.

Side effects and risks

Byetta and Bydureon both contain exenatide. Therefore, both medications can cause very similar side effects. Below are examples of these side effects.

More common side effects

These lists contain examples of more common side effects that can occur with Byetta, with Bydureon, or with both drugs (when taken individually).

  • Can occur with Byetta:
    • dizziness
    • feeling jittery
  • Can occur with Bydureon:
    • itching at the injection site
    • small bump (nodule) at the injection site
  • Can occur with both Byetta and Bydureon:
    • hypoglycemia (low blood sugar)
    • nausea
    • vomiting
    • diarrhea
    • constipation
    • indigestion
    • headaches
    • reduced appetite

Serious side effects

These lists contain examples of serious side effects that occur with Bydureon, and both Bydureon and Byetta (when taken individually).

  • Can occur with Bydureon:
    • severe injection-site reactions, such as abscess or cellulitis (infection in the deep layers of skin)
    • gallbladder problems, such as gallstones
    • risk of a certain type of thyroid cancer*
  • Can occur with both Byetta and Bydureon:
    • acute pancreatitis (inflammation of the pancreas)
    • severe allergic reaction
    • problems with kidney function, including kidney failure
* Bydureon has a boxed warning from the FDA about the risk of a certain type of thyroid cancer. A boxed warning is the strongest warning the FDA requires. It alerts doctors and patients about drug effects that may be dangerous.

Effectiveness

The only condition both Byetta and Bydureon are approved to treat is type 2 diabetes.

Byetta and Bydureon have been directly compared in a clinical study. In this study, the effectiveness of the drugs was compared when they were both used on their own and when they were used in combination with other diabetes drugs.

The study found that on average, Bydureon lowered hemoglobin by 0.7% more than Byetta over 24 weeks. Over the same time period, people treated with Bydureon had an average weight loss of 5 lbs.. People treated with Byetta lost an average of 3 lbs.

Costs

Byetta and Bydureon are both brand-name drugs. There are currently no generic forms of either drug. Brand-name medications usually cost more than generics.

According to estimates on GoodRx.com, Byetta and Bydureon generally cost about the same. The actual price you’ll pay for either drug depends on your insurance plan, your location, and the pharmacy you use.

Byetta and Victoza are prescribed for similar uses. Below are details of how these medications are alike and different.

Uses

Byetta and Victoza are both FDA-approved to help control blood sugar levels in adults with type 2 diabetes. They are both used along with a diet and exercise program.

Victoza is also FDA-approved to reduce the risk of heart attacks and strokes in people with type 2 diabetes who have heart disease.

Byetta contains exenatide, and Victoza contains liraglutide. These medications are from the same drug class, so they work in the same way in the body.

Drug forms and administration

Byetta and Victoza both come as a prefilled multidose injection pens.

With Byetta, you give yourself an injection under your skin (subcutaneously) twice a day, before your main meals. With Victoza, you give yourself an injection under your skin once a day, at any time of day.

Side effects and risks

Byetta and Victoza contain drugs from the same class. Therefore, both medications can cause very similar side effects. Below are examples of these side effects.

More common side effects

These lists contain examples of more common side effects that can occur with Byetta, with Victoza, or with both drugs (when taken individually).

  • Can occur with Byetta:
    • dizziness
    • feeling jittery
    • headaches
  • Can occur with Victoza:
    • upper respiratory tract infections
  • Can occur with both Byetta and Victoza:
    • hypoglycemia (low blood sugar)
    • nausea
    • vomiting
    • diarrhea
    • indigestion
    • constipation
    • reduced appetite

Serious side effects

These lists contain examples of serious side effects that can occur with Victoza, and with both Byetta and Victoza (when taken individually).

  • Can occur with Victoza:
    • gallbladder problems, such as gallstones
    • risk of certain types of thyroid cancer*
  • Can occur with both Byetta and Victoza:
    • acute pancreatitis (inflammation of the pancreas)
    • severe allergic reaction
    • problems with kidney function, including kidney failure
* Victoza has a boxed warning from the FDA about the risk of certain types of thyroid cancer. A boxed warning is the strongest warning the FDA requires. It alerts doctors and patients about drug effects that may be dangerous.

Effectiveness

Byetta and Victoza have slightly different FDA-approved uses, but they’re both used to improve blood sugar control in type 2 diabetes. They are both used along with a diet and exercise program.

Byetta and Victoza have been directly compared in a clinical study. In this study, the effectiveness of the drugs was compared when they were both used in combination with other drugs to treat diabetes (metformin, a sulfonylurea, or both).

The study found that, on average, Victoza lowered hemoglobin A1c (HbA1c) by 0.3% more than Byetta over 26 weeks. Over the same period, people treated with Victoza and people treated with Byetta both lost an average of 6.6 lbs..

Costs

Byetta and Victoza are both brand-name drugs. There are currently no generic forms of either drug. Brand-name medications usually cost more than generics.

According to estimates on GoodRx.com, Byetta is generally less expensive than Victoza. The actual price you’ll pay for either drug will depend on your insurance plan, your location, and the pharmacy you use.

The Food and Drug Administration (FDA) approves prescription drugs such as Byetta to treat certain conditions. Byetta may also be used off-label for other conditions. Off-label use is when a drug that’s approved to treat one condition is used to treat a different condition.

Byetta for type 2 diabetes

Byetta is FDA-approved to help control blood sugar levels in adults with type 2 diabetes. It’s used along with a diet and exercise program.

With diabetes, your body can’t control the amount of sugar (glucose) in your blood. This leads to high blood sugar levels.

Byetta reduces hemoglobin A1c (HbA1c), which is a measure of your average blood sugar levels over three months. Byetta helps lower your blood sugar after eating a meal. It also lowers your blood sugar between meals. This is called your fasting blood sugar level.

Byetta can also help some people lose weight. However, Byetta is not a weight loss drug and should not be used solely for this purpose.

Byetta may be used on its own or with other diabetes medications. These other medications include metformin, glipizide, and pioglitazone.

Effectiveness

In a clinical study of people using Byetta on its own:

  • average HbA1c was reduced by 0.7%–0.9% after 24 weeks, compared to 0.2% in people receiving a placebo (a treatment without an active drug)
  • average fasting blood sugar was reduced by 17–19 mg/dL after 24 weeks, compared with 5 mg/dL in people receiving a placebo
  • average weight loss was 6–6.4 lbs. (2.7–2.9 kg) after 24 weeks, compared to an average loss of 3.3 lbs. (1.5 kg) in people receiving a placebo

When used with another diabetes drug, Byetta is most often used with metformin. In a clinical study of people treated with Byetta and metformin:

  • average HbA1c was reduced by 0.5%–0.9% after 30 weeks, compared to 0% reduction in people receiving a placebo
  • average fasting blood sugar was reduced by 5–10 mg/dL, compared to an increase of 14 mg/dL in people receiving a placebo
  • average weight loss was 2.9–5.7 lbs. (1.3–1.6 kg) after 30 weeks, compared to an average loss of 0.4 lbs. (0.2 kg) in people receiving a placebo

Other possible uses for Byetta

Byetta only has FDA approval for helping control blood sugar in adults with type 2 diabetes.

Exenatide, the active drug in Byetta, is being investigated as a treatment for various other conditions, including polycystic ovary syndrome (PCOS), obesity, Parkinson’s disease, and type 1 diabetes. However, it’s not approved for any of these uses.

You take Byetta by giving yourself an injection under the skin (subcutaneously) of your upper arm, thigh, or abdomen. Your doctor will show you how to do this. You can find full instructions on how to prepare and use your injection pen in the user manual on the manufacturer’s website. You should always take Byetta according to your doctor’s instructions.

Talk with your doctor if you have questions about giving yourself the Byetta injection.

When to take

You should give yourself an injection of Byetta twice a day, in the hour before each of your two main meals. Most people give themselves one injection in the hour before breakfast, and another in the hour before dinner.

However, if you don’t eat much breakfast, you could choose to have your first injection in the hour before lunch. Your second injection would still be in the hour before your dinner, as long as these meals are at least six hours apart. Ask your doctor for advice if you’re not sure when to give yourself your injections.

Medication reminders can help make sure that you don’t miss a dose.

Taking Byetta with food

Byetta has to be taken in the hour before a meal. If you forget to inject it before your meal, don’t inject it after the meal. Just leave out that dose. Never use a double dose to make up for a missed dose.

Important points about using Byetta

  • Each Byetta pen contains enough medication to give yourself one dose twice a day for 30 days. The pen measures each dose automatically.
  • Byetta doesn’t come with needles, so you will need to get these separately. Needles come in different sizes, so talk to your doctor about which needle size you will need.
  • You should use a new needle each time you give yourself an injection. Safely dispose of each needle in a sharps container after use. Don’t store your pen with a needle attached.
  • Never share your Byetta pen with anyone else, even if you’ve changed the needle. Sharing the pen could promote the spread of infections.
  • If you are using insulin as well as Byetta, take them as two separate injections. Don’t mix Byetta with insulin in the same syringe.

Drinking too much alcohol can cause your blood sugar level to fall. Using alcohol while taking Byetta could raise your risk of hypoglycemia (having your blood sugar level fall too low).

If you drink alcohol, talk with your doctor about how much alcohol is safe to drink while you are using Byetta.

Byetta can interact with several other medications.

Different interactions can cause different effects. For instance, some interactions can interfere with how well a drug works. Other interactions can increase side effects or make them more severe.

Byetta and other medications

Below is a list of medications that can interact with Byetta. This list does not contain all drugs that may interact with Byetta.

Before taking Byetta, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Drugs you take by mouth

Byetta makes your stomach empty more slowly. Because of this, you should try to avoid taking medications by mouth for a few hours after giving yourself the Byetta injection. If you do take them during that time, the drugs you’ve taken by mouth may not be absorbed into your body as well. This could make them less effective.

If you need to take medications by mouth, it’s best to take them at least one hour before having your Byetta injection. This gives them time to pass through your stomach and be absorbed through your small intestine. This is particularly important for antibiotics (drugs used to treat bacterial infections) and birth control pills. If you are supposed to take your other medications with a meal, you should take them with a meal when you are not having a Byetta injection.

Talk to your pharmacist if you need help deciding when to take your other medications.

Other drugs for diabetes that increase insulin

You may use Byetta with other drugs for your diabetes. If you use other drugs that increase your insulin levels, you’re more likely to develop low blood sugar levels (hypoglycemia). Your doctor may need to reduce the doses of your other drugs to avoid this.

Other medications that increase insulin include:

  • insulin degludec (Tresiba)
  • insulin detemir (Levemir)
  • insulin glargine (Lantus, Toujeo)
  • glimepiride (Amaryl)
  • glipizide (Glucotrol)
  • glyburide (DiaBeta, Glynase)

Warfarin

Byetta might increase the anti-blood-clotting effect of warfarin (Coumadin, Jantoven).

If you use Byetta with warfarin, this could increase your risk of bleeding. Your doctor may want to check how long it takes your blood to clot after you start treatment with Byetta and after any dose increases. Depending on the results, your doctor may reduce your warfarin dose.

Byetta and metformin

Byetta can be used with metformin (Glucophage, Fortamet, Glumetza, Riomet) to treat type 2 diabetes. This combination is safe to use together.

Based on the clinical trial, using Byetta with metformin probably won’t make you more likely to get low blood sugar.

Byetta and Januvia

Byetta hasn’t been studied with Januvia. However, Januvia works in a similar way to Byetta, so your doctor probably wouldn’t prescribe you both drugs.

Byetta and herbs and supplements

There aren’t any herbs or supplements that have been specifically reported to interact with Byetta. However, you should still check with your doctor or pharmacist before using any of these products while taking Byetta.

There’s not enough data available to say if Byetta is safe to use during pregnancy. Studies in animals have shown some harmful effects on the fetus of a pregnant female given the drug. However, animal studies do not always predict what will happen in humans.

It’s important to note that if diabetes is poorly controlled during pregnancy, it can carry risks for the mother and baby. So it’s important to create a plan with your doctor to manage your diabetes if you are, or will be, pregnant.

Before you start using Byetta, let your doctor know if you are pregnant or think you could be pregnant. If you are planning a pregnancy, talk with your doctor about the possible risks and benefits of using Byetta.

It’s not known if Byetta passes into breast milk. If you would like to breastfeed while using Byetta, talk with your doctor about the possible risks and benefits.

Using more than the recommended dosage of Byetta can lead to serious side effects.

Overdose symptoms

Symptoms of an overdose can include:

  • severe nausea
  • severe vomiting
  • rapid drop in blood sugar levels (hypoglycemia), which can cause symptoms such as:
    • fast heartbeat
    • sweating
    • pale skin
    • feeling weak or tired
    • hunger
    • headache
    • confusion
    • sudden mood changes

What to do in case of overdose

If you think you’ve taken too much of Byetta, call your doctor. You can also call the American Association of Poison Control Centers at 800-222-1222 or use their online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.

If you have type 2 diabetes, your body has trouble controlling the level of sugar (glucose) in your blood.

This is because the cells in your body have built up a resistance to the effects of insulin. Insulin is the main hormone responsible for lowering your blood sugar levels. Over time, your body may also produce less insulin.

How your body usually controls blood sugar

Insulin is the key hormone that lowers your blood sugar levels, but it’s not the only hormone involved.

When you eat, your small intestine produces a hormone called GLP-1. As the food starts to be absorbed into your blood, the level of glucose (sugar) in your blood starts to rise. GLP-1 stimulates your pancreas to release insulin into your bloodstream in response to the rise in blood sugar. Insulin directs cells in your body to remove glucose from your blood, and this lowers your blood sugar level.

GLP-1 also has some other actions that help control your blood sugar. It stops your pancreas from releasing a hormone called glucagon. Glucagon normally makes your liver produce glucose. If less glucagon is produced, it lowers your blood sugar level.

In addition, GLP-1 also helps regulate your appetite. It slows down the speed that food moves through your stomach and into your small intestine. This makes you feel fuller sooner. GLP-1 also acts in your brain to reduce your appetite.

What Byetta does

The active ingredient in Byetta is called exenatide. This is a type of drug called a glucagon-like peptide-1 (GLP-1) receptor agonist.

Byetta acts in a similar way to the hormone called GLP-1 that your intestine releases when you eat. This means it produces the same four effects as GLP-1:

  • It makes your pancreas release more insulin, which removes glucose from your blood.
  • It makes your pancreas release less glucagon, which stops your liver from making glucose.
  • It slows down the passage of food out of your stomach and into your small intestine, so glucose is absorbed into your bloodstream more slowly.
  • It reduces your appetite, so you don’t eat as much.

These actions allow Byetta to help lower your blood sugar level after eating a meal and keep it lower between meals.

How long does it take to work?

Byetta starts to work as soon as you inject a dose. It keeps building up an effect over the next couple of hours.

Here are answers to some frequently asked questions about Byetta.

Is Byetta the same as meal-time insulin?

No. Byetta has a similar effect to meal-time insulin (fast-acting insulin) because it makes your body produce more insulin in response to a meal. However, it also has other effects that help control your blood sugar between meals, as well as immediately after meals.

Will I need to use insulin with Byetta?

You won’t need to use insulin with Byetta unless your doctor prescribes it. This depends on your individual situation.

If your blood sugar can be controlled well enough by using Byetta, then your doctor won’t need to prescribe other medication. If Byetta doesn’t control your blood sugar enough, your doctor may need to prescribe extra treatment to get your blood sugar down. They may prescribe one of the many type 2 diabetes drugs that are now available, or they may prescribe insulin. Insulin can be used for both type 2 and type 1 diabetes.

If you’re already using insulin and your doctor suggests adding Byetta to your treatment, you’ll need to follow their instructions. Byetta can be used along with a long-acting insulin such as insulin glargine. However, Byetta is not recommended for use with meal-time insulins.

If I have type 1 diabetes, can I use Byetta?

Type 1 diabetes has to be treated with insulin injections. Although Byetta is given by injection, it’s not the same as insulin.

Byetta works primarily by making your pancreas produce more insulin. If you have type 1 diabetes, the cells in your pancreas can’t make insulin. Therefore, the main way that Byetta lowers blood sugar won’t work for you.

Byetta is not approved for type 1 diabetes, and the current medical opinion is that it shouldn’t be used for type 1 diabetes.

Byetta has other effects, such as making your stomach empty more slowly and helping you lose weight. This means it could have potential as an add-on treatment for some people with type 1 diabetes. Those who might benefit include people whose blood sugar is not well controlled by insulin and people who could benefit from weight loss. One study in type 1 diabetes found that adding Byetta to insulin improved blood sugar control more than insulin alone.

However, Byetta is currently only approved to treat type 2 diabetes.

Is Byetta used to treat PCOS?

Byetta is not FDA-approved to treat polycystic ovary syndrome (PCOS). However, exenatide was shown in one study to help with weight loss, improve insulin sensitivity (the way cells respond to insulin), and encourage more regular periods in women with PCOS.

Can I switch from Byetta to Bydureon?

Yes. You could switch from Byetta to Bydureon if your doctor thinks it would work better for your specific health situation. Also, Bydureon could be more convenient because you only have to inject it once a week instead of twice a day.

Talk with your doctor if you’re interested in switching from Byetta to Bydureon.

It’s important to note that when you first switch to Bydureon, your blood sugar levels may rise temporarily (for the first two to four weeks).

Before taking Byetta, talk with your doctor about your health history. Byetta may not be right for you if you have certain medical conditions. These include:

  • Pancreatitis. If you’ve ever had pancreatitis (inflammation of your pancreas), Byetta may not be right for you. A few people using Byetta have experienced acute pancreatitis, and in some cases this was serious or fatal. It’s not known if you’re more likely to get pancreatitis with Byetta if you’ve had the condition before. Your doctor will likely recommend a different diabetes drug if you’ve had pancreatitis in the past. If you get pancreatitis while using Byetta, you’ll need to stop using it.
  • Problems with your kidneys, or a previous kidney transplant. It may be possible for you to use Byetta. However, Byetta could stop your kidneys from working as well. If this happens, you may need to stop treatment. You may not be able to use Byetta if you’ve had severe kidney problems such as end-stage kidney (renal) failure.
  • Certain digestive problems. Tell your doctor if you have disorders that affect your digestive system, such as delayed stomach emptying (gastroparesis) or problems with digestion. Byetta commonly causes nausea, vomiting, and diarrhea, which could make your condition worse. If this happens, you may need to stop using Byetta.

Note: For more information about the potential negative effects of Byetta, see the “Byetta side effects” section above.

Each Byetta package and pen will have an expiration date printed on it. Don’t use Byetta if the date is beyond this expiration date.

The expiration date helps guarantee the medication is effective during this time. The current stance of the Food and Drug Administration (FDA) is that you should avoid using expired medications. If you have unused medication that has gone past the expiration date, talk to your pharmacist about whether you might still be able to use it.

Each Byetta pen can be used for 30 days. If there is medication left in the pen 30 days after you first use it, safely dispose of it in a sharps disposal container. See the “Disposal” section below for more information.

Storage

How long a medication remains good can depend on many factors, including how and where you store it.

Before you use your Byetta pen for the first time, keep it in a refrigerator at 36°F–46°F (2°C–8°C). Keep it in the box it came in. Avoid freezing your pens. Byetta pens can’t be used if they have been frozen.

Once you start using a Byetta pen, you can keep it out of the refrigerator at room temperature no higher than 77°F (25°C). Always remove the needle and put the pen cap back on after you inject a dose of Byetta. The cap protects the drug from light.

Don’t store your Byetta pen with a needle attached.

Disposal

If you no longer need to take Byetta and have leftover medication, it’s important to dispose of it safely. This helps prevent others, including children and pets, from taking the drug by accident. It also helps keep the drug from harming the environment.

The FDA website provides several useful tips on medication disposal. You can also ask your pharmacist how to dispose of your medication.

The following information is provided for clinicians and other healthcare professionals.

Indications

Byetta is FDA-approved to help control blood glucose levels in adult patients with type 2 diabetes, as an adjunct to diet and exercise.

Byetta has been studied as monotherapy for type 2 diabetes. It’s also been studied in combination therapy with the following:

  • metformin
  • a sulfonylurea
  • a thiazolidinedione
  • metformin plus sulfonylurea
  • metformin plus thiazolidinedione
  • insulin glargine with or without metformin and/or thiazolidinedione

Byetta should not be prescribed to control blood sugar in type 1 diabetes or diabetic ketoacidosis.

Mechanism of action

Byetta contains exenatide, a glucagon-like peptide-1 (GLP-1) receptor agonist or incretin mimetic.

It activates the GLP-1 receptor on beta cells in the pancreas, stimulating insulin release in response to rising glucose levels and reducing the release of glucagon. In addition, Byetta slows down gastric emptying, thereby reducing the rate at which mealtime glucose is absorbed into the bloodstream. It reduces appetite and intake of food.

Byetta increases first-phase and second-phase insulin response and reduces postprandial and fasting glucose levels.

Pharmacokinetics and metabolism

Byetta has similar bioavailability when administered in the thigh, abdomen, or upper arm. It reaches median peak plasma concentration in 2.1 hours.

Byetta is mainly renally excreted through glomerular filtration. It has a mean terminal half-life of 2.4 hours.

The pharmacokinetics of Byetta are not affected by age. The influence of hepatic function on Byetta has not been studied, but it’s unlikely to have an effect because the drug is mainly cleared renally.

Contraindications

Byetta should not be used in people who have had a hypersensitivity reaction to exenatide or any of the excipients.

Storage

Before the first use, Byetta should be stored in its original packaging in a refrigerator at 36°F–46°F (2°C–8°C). Do not freeze Byetta, and don’t use if it has been frozen.

After the first use, Byetta can be stored at room temperature, below 77°F (25°C), for up to 30 days. When not in use, pens should be stored without a needle attached and with the cap on.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.