Januvia (Merck & Co.)

Januvia (Merck & Co.) - General Information

Januvia (Merck & Co.) is a new oral hypoglycemic (anti-diabetic drug) of the new dipeptidyl peptidase-4 (DPP-4) inhibitor class of drugs. This enzyme-inhibiting drug is to be used either alone or in combination with metformin or a thiazolidinedione for control of type 2 diabetes mellitus. The drug works to competitively inhibit a protein/enzyme, dipeptidyl peptidase 4 (DPP-4), that results in an increased amount of active incretins (GLP-1 and GIP), reduced amount of release of glucagon (diminishes its release) and increased release of insulin.


Pharmacology of Januvia (Merck & Co.)

Januvia (Merck & Co.) is an orally-active member of the new dipeptidyl peptidase-4 (DPP-4) inhibitor class of drugs. The benefit of this medicine is expected to be its lower side-effects of hypoglycemia in the control of blood glucose values. The drug works to diminish the effects of a protein/enzyme (by the inhibition of this protein/enzyme) on the pancreas at the level of release of glucagon (diminishes its release) and at the level of insulin (increases its synthesis and release) until blood glucose levels are restored toward normal, in which case the protein/enzyme-enzyme inhibitor becomes less effective and the amounts of insulin released diminishes thus diminishing the "overshoot" of hypoglycemia seen in other oral hypoglycemic agents.


Januvia (Merck & Co.) for patients

JANUVIA™ (jah-NEW-vee-ah)
(sitagliptin phosphate)

Read the Patient Information that comes with JANUVIA* before you start taking it and each time you get a refill. There may be new information. This leaflet does not take the place of talking with your doctor about your medical condition or treatment.

What is JANUVIA?

JANUVIA is a prescription medicine used along with diet and exercise to lower blood sugar in patients with type 2 diabetes mellitus (type 2 diabetes). JANUVIA may be taken alone or along with certain other medicines to control blood sugar.

  • JANUVIA lowers blood sugar when blood sugar is high, especially after a meal. JANUVIA also lowers blood sugar between meals.
  • JANUVIA helps to improve the levels of insulin produced by your own body after a meal.
  • JANUVIA decreases the amount of sugar made by the body. JANUVIA is unlikely to cause your blood sugar to be lowered to a dangerous level (hypoglycemia) because it does not work when your blood sugar is low.

JANUVIA has not been studied in children under 18 years of age.

JANUVIA has not been studied with medicines known to cause low blood sugar, such as sulfonylureas or insulin. Ask your doctor if you are taking a sulfonylurea or other medicine that can cause low blood sugar.

Who should not take JANUVIA?

JANUVIA should not be used to treat patients with:

  • Type 1 diabetes mellitus
  • Diabetic ketoacidosis (increased ketones in the blood or urine).

What should I tell my doctor before and during treatment with JANUVIA?

Tell your doctor about all of your medical conditions, including if you:

  • have any allergies
  • have kidney problems
  • are pregnant or plan to become pregnant, because JANUVIA may not be right for you. It is not known if JANUVIA will harm your unborn baby. If you are pregnant, talk with your doctor about the best way to control your blood sugar while you are pregnant. If you use JANUVIA during pregnancy, talk with your doctor about how you can be on the JANUVIA registry. The toll-free telephone number for the pregnancy registry is: 1-800-986-8999.
  • are breast-feeding or plan to breast-feed. JANUVIA may be passed in your milk to your baby.

Talk with your doctor about the best way to feed your baby if you are taking JANUVIA.

Tell your doctor about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements.

Know the medicines you take. Keep a list of your medicines and show it to your doctor and pharmacist when you get a new medicine.

During periods of stress on the body, such as fever, trauma, infection or surgery, your medication needs may change; contact your doctor right away.

How should I take JANUVIA?

  • Take JANUVIA exactly as your doctor tells you to take it.
  • Take JANUVIA by mouth once a day.
  • Take JANUVIA with or without food.
  • If you have kidney problems, your doctor may prescribe lower doses of JANUVIA. Your doctor may perform blood tests on you from time to time to measure how well your kidneys are working.
  • Your doctor may prescribe JANUVIA along with certain other medicines that lower blood sugar.

If you miss a dose, take it as soon as you remember. If you do not remember until it is time for your next dose, skip the missed dose and go back to your regular schedule. Do not take a double dose of JANUVIA.

If you take too much JANUVIA, call your doctor or local Poison Control Center right away.

What else should I know about blood sugar control?

  • Monitor your blood sugar as your doctor tells you to.
  • Stay on your prescribed diet and exercise program while taking JANUVIA.
  • Talk to your doctor about how to prevent, recognize and manage low blood sugar (hypoglycemia), high blood sugar (hyperglycemia), and complications of diabetes.
  • Your doctor will monitor your diabetes with regular blood tests, including your blood sugar levels and your hemoglobin A1C.

What are the possible side effects of JANUVIA?

The most common side effects of JANUVIA include:

  • Upper respiratory infection
  • Stuffy or runny nose and sore throat
  • Headache

JANUVIA may occasionally cause stomach discomfort and diarrhea.

Tell your doctor if you have any side effect that bothers you or that does not go away.

Other side effects may occur when using JANUVIA. For more information, ask your doctor or pharmacist.

How Should I store JANUVIA?

  • Store JANUVIA at room temperature, 68 to 77°F (20 to 25°C).

Keep JANUVIA and all medicines out of the reach of children.

General information about the use of JANUVIA

Medicines are sometimes prescribed for conditions that are not mentioned in patient information leaflets. Do not use JANUVIA for a condition for which it was not prescribed. Do not give JANUVIA to other people, even if they have the same symptoms you have. It may harm them.

This leaflet summarizes the most important information about JANUVIA. If you would like to know more information, talk with your doctor. You can ask your doctor or pharmacist for additional information about JANUVIA that is written for health professionals. For more information go to OR CALL 1-800-622-4477.

What are the ingredients in JANUVIA?

Active ingredient: sitagliptin phosphate

Inactive ingredients: microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, magnesium stearate, and sodium stearyl fumarate. The tablet film coating contains the following inactive ingredients: polyvinyl alcohol, polyethylene glycol, talc, titanium dioxide, red iron oxide, and yellow iron oxide.

What is type 2 diabetes?

Type 2 diabetes is a condition in which your body does not make enough insulin, and the insulin that your body produces does not work as well as it should. Your body can also make too much sugar. When this happens, sugar (glucose) builds up in the blood. This can lead to serious medical problems.

The main goal of treating diabetes is to lower your blood sugar to a normal level. Lowering and controlling blood sugar may help prevent or delay complications of diabetes, such as heart disease, kidney disease, blindness, and amputation.

High blood sugar can be lowered by diet and exercise, and by certain medicines when necessary.


Januvia (Merck & Co.) Interactions


There was a slight increase in the area under the curve (AUC, 11%) and mean peak drug concentration (Cmax, 18%) of digoxin with the co-administration of 100 mg sitagliptin for 10 days. Patients receiving digoxin should be monitored appropriately. No dosage adjustment of digoxin or JANUVIA is recommended.


Januvia (Merck & Co.) Contraindications


Additional information about Januvia (Merck & Co.)

Januvia (Merck & Co.) Indication: For use as an adjunct to diet and exercise to improve glycemic control in patients with type 2 diabetes mellitus. Also for use in patients with type 2 diabetes mellitus to improve glycemic control in combination with metformin or a PPARγ agonist (e.g., thiazolidinediones) when the single agent alone, with diet and exercise, does not provide adequate glycemic control.
Mechanism Of Action: Januvia (Merck & Co.) is a DPP-4 inhibitor, which is believed to exert its actions in patients with type 2 diabetes by slowing the inactivation of incretin hormones. Concentrations of the active intact hormones are increased by sitagliptin, thereby increasing and prolonging the action of these hormones. Incretin hormones, including glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), are released by the intestine throughout the day, and levels are increased in response to a meal. These hormones are rapidly inactivated by the enzyme, DPP-4. The incretins are part of an endogenous system involved in the physiologic regulation of glucose homeostasis. When blood glucose concentrations are normal or elevated, GLP-1 and GIP increase insulin synthesis and release from pancreatic beta cells by intracellular signaling pathways involving cyclic AMP. GLP-1 also lowers glucagon secretion from pancreatic alpha cells, leading to reduced hepatic glucose production. By increasing and prolonging active incretin levels, sitagliptin increases insulin release and decreases glucagon levels in the circulation in a glucose-dependent manner. Januvia (Merck & Co.) demonstrates selectivity for DPP-4 and does not inhibit DPP-8 or DPP-9 activity in vitro at concentrations approximating those from therapeutic doses.
Drug Interactions: Not Available
Food Interactions: Not Available
Generic Name: Sitagliptin
Synonyms: MK-0431; Sitagliptin phosphate; Sitagliptan
Drug Category: Hypoglycemic Agents
Drug Type: Small Molecule; Approved

Other Brand Names containing Sitagliptin: Januvia (Merck & Co.); Xelevia;
Absorption: Rapidly absorbed following oral administration, with an absolute bioavailability of 87%.
Toxicity (Overdose): Not Available
Protein Binding: The fraction of sitagliptin reversibly bound to plasma proteins is low (38%).
Biotransformation: Hepatic. In vitro studies indicated that the primary enzyme responsible for the limited metabolism of sitagliptin was CYP3A4, with contribution from CYP2C8.
Half Life: 12.4 hours
Dosage Forms of Januvia (Merck & Co.): Tablet, film coated Oral
Chemical IUPAC Name: (3R)-3-amino-1-[3-(trifluoromethyl)-6,8-dihydro-5H-[1,2,4]triazolo[3,4-c]pyrazin-7-yl]-4-(2,4,5-trifluorophenyl)butan-1-one
Chemical Formula: C16H15F6N5O
Sitagliptin on Wikipedia:
Organisms Affected: Humans and other mammals