Sitagliptin/metformin (By mouth)

Metformin Hydrochloride (met-FOR-min hye-droe-KLOR-ide), Sitagliptin Phosphate (sit-a-GLIP-tin FOS-fate)

Treats type 2 diabetes.

Brand Name(s):

Janumet, Janumet XR

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. Do not use it if you had an allergic reaction to metformin or sitagliptin.

How to Use This Medicine:

Tablet, Long Acting Tablet

  • Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
  • It is best to take this medicine with food or milk.
  • Extended-release tablet:
    • Take this medicine in the evening.
    • You may see tablets in your stools. If this happens several times, tell your doctor right away.
  • Swallow the tablet whole. Do not crush, break, or chew it.
  • Drink plenty of fluids to help prevent dehydration.
  • This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
  • Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some medicines can affect how metformin/sitagliptin works. Tell your doctor if you are using any of the following:
    • Cimetidine, digoxin, dolutegravir, morphine, phenytoin, quinine, ranitidine, ranolazine, vandetanib
    • Blood pressure medicine (including amiloride)
    • Diuretic (water pill, including acetazolamide, dichlorphenamide, triamterene)
    • Insulin or other diabetes medicine
    • Medicine for heart rhythm changes (including procainamide, quinidine)
    • Medicine to treat infections (including isoniazid, rifampin, trimethoprim, vancomycin)
    • Medicine to treat seizures (including phenytoin, topiramate, zonisamide)
  • Some medicines may affect your blood sugar level, including a diuretic (water pill), birth control pills, corticosteroid (including dexamethasone, hydrocortisone, methylprednisolone, prednisolone, prednisone), phenothiazine medicine (including chlorpromazine, perphenazine, prochlorperazine, promethazine, thioridazine), thyroid medicine, niacin, and isoniazid. Closely monitor your blood sugar levels when you start or stop another medicine while you are using sitagliptin/metformin.
  • Limit the amount of alcohol you drink while you are using this medicine. Heavy alcohol use increases your risk for lactic acidosis.

Warnings While Using This Medicine:

  • Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, heart disease, adrenal or pituitary gland disease, high cholesterol, vitamin B12 deficiency, or a history of heart failure or pancreatitis.
  • This medicine may cause the following problems:
    • Lactic acidosis (too much acid in the blood, which can be life-threatening)
    • Pancreatitis (inflammation of the pancreas)
    • Heart failure
    • Kidney problems
    • Low levels of vitamin B12 in the blood
    • Low blood sugar
    • Serious skin reactions
  • Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may interact with the dye used for an x-ray or a CT scan.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Blistering, peeling, red skin rash
  • Change in how much or how often you urinate
  • Fast breathing, trouble breathing, nausea and vomiting, lightheadedness, severe weakness, tiredness, confusion
  • Large, hard skin blisters
  • Paleness, feeling tired or weak
  • Severe joint pain
  • Shaking, trembling, sweating, fast or pounding heartbeat, faintness, hunger, confusion
  • Sudden and severe stomach pain, nausea, vomiting, fever, lightheadedness
  • Swelling in your hands, ankles, or feet
  • Trouble breathing, cold sweat, bluish-colored skin

If you notice these less serious side effects, talk with your doctor:

  • Cough, stuffy or runny nose, sore throat
  • Diarrhea

If you notice other side effects that you think are caused by this medicine, tell your doctor

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

Last Updated: 11/6/2020

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