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Medications

JANUVIA (sitagliptin)* is the first drug in a new class called dipeptidyl peptidase IV (or DPP-4) inhibitors.  Please first read about BYETTA in the related question listed on the right side of this page - so you can learn more about GLP-1.   JANUVIA, as a DPP-4 inhibitor, enhances your body's level of GLP-1. So while BYETTA is a synthetic version of GLP-1, JANUVIA is an enhancer of GLP-1.

• As a background reminder:  People with type 2 diabetes are deficient in the hormone GLP-1. Normally, within 10 minutes of eating, GLP-1 is released to enhance insulin secretion after eating, as well as to suppress glucagon-another hormone in the pancreas that tells the liver to release glucose. This is called "glucose dependent secretion" meaning that insulin is supposed to be secreted quickly and only when needed, and glucagon is supposed to be suppressed when the liver does not need to release glucose (such as during a meal).

How Does JANUVIA Work:

• There is an enzyme in the body called DPP-4, which rapidly deactivates GLP-1. You will read in the related question about BYETTA that GLP-1 is an incretin that slows stomach emptying, stimulates insulin production in response to a meal, and suppresses glucagon.  So by inhibiting the action of DPP-4, your own GLP-1 levels rise, making your body more able to regulate insulin and suppress glucagon.
• This means that JANUVIA lowers your blood glucose when your blood glucose is high, especially after a meal; it also lowers blood glucose between meals.
• JANUVIA helps to improve the levels of insulin produced by your own body after a meal, plus it decreases the amount of sugar made by the liver.
• Note that like BYETTA, JANUVIA is unlikely to cause your blood glucose to go too low (hypoglycemia) because it does not work when your blood glucose is low.

Who Can Take JANUVIA:

• Adults with type 2 diabetes
• People with type 2 diabetes who are also taking metformin (Glucophage®), a sulfonylurea, or a thiazolidinedione (such as Avandia® or Actos®).

Who Should NOT Take JANUVIA:

• People with type 1 diabetes.
• People who are in diabetic ketoacidosis.
• NOTE: JANUVIA has not been studied in pregnant women or children under 18 years of age.
• Also, talk to your doctor if you have any kidney problems, as your doctor will check your kidney function, and may need to prescribe a lower dose of JANUVIA.

How Do You Take JANUVIA:

• According to the patient instructions for use on the JANUVIA web site, JANUVIA is taken once daily, with or without food.
• NOTE: The FDA has also approved a combination pill called JANUMET™, which is a combination of JANUVIA and metformin (Glucophage®) in one pill; JANUMET is taken twice daily.
  

What are the Possible Side Effects of JANUVIA:

• Upper respiratory infection
• Stuffy or runny nose and sore throat
• Headache
• NOTE: the July 11, 2007 issue of the Journal of the American Medical Association reported an increased risk of urinary tract infections in people taking JANUVIA. The authors recommended that until further studies of longer duration can be completed, that this drug should be avoided in those with a history of recurrent urinary tract infections. Likewise, they suggested that it may be wise to avoid use of this drug in those with a history of chronic headaches.

How Does JANUVIA differ from BYETTA:

• Beside the fact that these drugs work by different mechanisms, the main differences are:
  • BYETTA is given by injection, twice daily, within an hour before a meal, while JANUVIA is a pill taken by mouth once a day.
  • While most people lose weight on BYETTA there is neither weight gain nor weight loss when you take JANUVIA.
  • BYETTA causes nausea for some people, especially when they start the drug, while JANUVIA does not cause nausea.
  • BYETTA is indicated for treatment of people with type 2 diabetes who are already on certain other medications but who have not yet achieved good diabetes control; JANUVIA is indicated as an earlier treatment - i.e. it can be the first drug with which you are treated, depending on your healthcare professional's advice.

Summary:

There are several recent new developments in diabetes, with several entirely new types of diabetes drugs. It can be confusing sorting out which is the best treatment regimen for you, and as you can see, each drug has specific indications, positive effects, and sometimes side effects as well. Experts are still analyzing the effects of all of these developments, so stay tuned as more information becomes available.

I have provided only the most important information. After you have reviewed this information, please talk to your healthcare team to see if it is right for you. Should you decide to try JANUVIA, note that this is a prescription drug, and that you should obtain instruction and guidance from a trained healthcare professional.

* Resources for this answer are from the JANUVIA website, the JANUVIA patient information, the JANUMET website, Diabetes Health, DOC News, Dec. 2006.