What is Byetta? What does it do?

Byetta is a brand name of the drug exenatide, which is used to treat type 2 diabetes. Exenatide stimulates the pancreas to secrete insulin when blood sugar levels are high, which helps move sugar out of the blood and into other body tissues, where it can be used for energy. This drug is dispensed from an injection pen.¹

Byetta is sold in the United States by Amylin Pharmaceuticals, Inc. and Eli Lilly and Company.²

Does Byetta work?

A study of type 2 diabetes patients on a 52-week trial concluded that exenatide (Byetta) significantly improved blood glucose levels. This study was funded by the manufacturers of Byetta.³

Some patients taking Byetta reported that it controlled their blood sugar, they were well satisfied with its performance and they were happy to experience weight loss while taking the drug. Other patients reported experiencing adverse effects, including weakness and dizziness, but some of those patients were also happy with Byetta’s performance in lowering blood sugar levels.⁴

What should I go over with my doctor before I decide to take Byetta?

From April 2005 through October 2008, the FDA received 78 cases of altered kidney function (62 cases of acute renal failure and 16 cases of renal insufficiency), in patients using Byetta. Some cases occurred in patients with pre-existing kidney disease or in patients with one or more risk factors for developing kidney problems. From April 2005 through September 2008, more than 6.6 million prescriptions for Byetta were dispensed. Therefore, the 78 reported cases of altered renal function represent a small percentage of the total number of patients who have used the drug. Some of the 78 patients reported nausea, vomiting, and diarrhea–the most common side effects associated with Byetta in clinical trials. These side effects may have contributed to the development of altered kidney function in the reported cases.⁵

A 2010 review of reported adverse events on the US Food and Drug Adminstration database of reported adverse events concluded that reports of pancreatitis and pancreatic cancer among human patients were consistent with results of animal studies. The review stated that “pancreatic cancer was more commonly reported among patients who took sitagliptin or exenatide as compared with other therapies.” ⁶

Byetta is not a substitute for insulin and should not be taken by patients suffering from type 1 diabetes.⁷

Patients taking Byetta have experienced cases of pancreatitis.⁸

Some patients may be allergic to Byetta and there have been rare reports of anaphylactic reactions (a life-threatening type of allergic reaction).⁹

Less serious side effects of Byetta can include nausea, vomiting, diarrhea, dehydration, abdominal swelling and pain, constipation and flatulence.¹⁰

What if I’m already taking Byetta?

Byetta may react with other medications, in some cases reducing those medications' effectiveness. It is possible to overdose with Byetta and symptoms include severe nausea, severe vomiting, rapidly lowering blood glucose levels and the possibility of developing hypoglycemia (low blood sugar).¹¹

Never stop taking a prescription medication without talking to your doctor. If you’re concerned about Byetta or experience any adverse reaction, talk to your doctor.

Learn everything you can about Byetta before you start taking it.

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¹ PubMed Health, “Exenatide Injection,” (revised 15 June 2011, retrieved 29 October 2012), http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000317/
² http://www.byetta.com; FiercePharma, Staton T., “Amylin gets Byetta custody in split with Lilly” (8 November 2011), http://www.fiercepharma.com/story/amylin-gets-byetta-custody-split-lilly/2011-11-08
³ Diabetes Care, Bunck M. et al., “One-Year Treatment With Exenatide Improves ?-Cell Function, Compared With Insulin Glargine, in Metformin-Treated Type 2 Diabetic Patients” (5 February 2009), http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2671094/
⁴ Healing Well, Patient Forums (retrieved 30 October 2012), http://www.healingwell.com/community/default.aspx?f=20&m=290518
⁵ Food and Drug Administration, “Exenatide (marketed as Byetta) Information” (Last Updated: 11/13/2009), http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm113705.htm
⁶ Gastroenterology, Hillblom L. et al.. “Pancreatitis, Pancreatic, and Thyroid Cancer With Glucagon-Like Peptide-1–Based Therapies” (21 February 2011), http://www.gastrojournal.org/article/S0016-5085(11)00172-7/abstract
⁷ Food and Drug Administration, (11 January 2008), http://www.accessdata.fda.gov/drugsatfda_docs/label/2008/021773s012lbl.pdf
⁸ Ibid.
⁹ Ibid.
¹⁰ Ibid.
¹¹ Ibid.