Generic Name: metformin and sitagliptin (met FOR min and SI ta glip tin)Brand Names: Janumet
Metformin and sitagliptin are oral diabetes medicines that help control blood sugar levels.
Metformin works by decreasing glucose (sugar) production in the liver and decreasing absorption of glucose by the intestines.
Sitagliptin works by regulating the levels of insulin your body produces after eating.
The combination of metformin and sitagliptin is for people with type 2 diabetes who do not use daily insulin injections. This medication is not for treating type 1 diabetes.
Metformin and sitagliptin may also be used for other purposes not listed in this medication guide.
Before taking metformin and sitagliptin, tell your doctor if you have liver or kidney disease, a history of pancreatitis, a history of heart disease, or if you are over 80 years old and have not recently had your kidney function checked.Stop taking metformin and sitagliptin and call your doctor at once if you have severe pain in your upper stomach spreading to your back, nausea and vomiting, loss of appetite, or fast heart rate. Some people have developed a life-threatening condition called lactic acidosis while taking metformin. Get emergency medical help if you have any of these symptoms of lactic acidosis: muscle pain or weakness, numb or cold feeling in your arms and legs, trouble breathing, stomach pain, nausea with vomiting, slow or uneven heart rate, dizziness, or feeling very weak or tired. Avoid drinking alcohol while taking metformin and sitagliptin.
If you need to have any type of x-ray or CT scan using a dye that is injected into a vein, you may need to temporarily stop taking metformin and sitagliptin.
You may be more likely to develop lactic acidosis if you have liver disease, kidney disease, congestive heart failure, a stroke or heart attack, a serious infection, if you are dehydrated, or if you drink large amounts of alcohol. Talk with your doctor about your individual risk.Do not use this medication if you are allergic to metformin (Actoplus Met, Avandamet, Fortamet, Glucophage, Riomet) or sitagliptin (Januvia), if you have kidney disease, or if you are in a state of diabetic ketoacidosis (call your doctor for treatment with insulin).
If you need to have any type of x-ray or CT scan using a dye that is injected into a vein, you will need to temporarily stop taking metformin and sitagliptin. Be sure the doctor knows ahead of time that you are using this medication.
If you have any of these other conditions, you may need a dose adjustment or special tests to safely take metformin and sitagliptin:
a history of pancreatitis;
a history of heart disease; or
if you are over 80 years old and have not recently had your kidney function checked.
If you have any of these conditions, you may need a dose adjustment or special tests to safely take this medication.FDA pregnancy category B. This medication is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.
Your name may need to be listed on a Janumet pregnancy registry if you become pregnant while you are taking this medication. The purpose of this registry is to track the outcome of the pregnancy and delivery to evaluate whether metformin and sitagliptin had any effect on the baby.It is not known whether metformin and sitagliptin passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby. Metformin and sitagliptin should not be given to a child younger than 18 years old without a doctor's advice.
Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.
Metformin and sitagliptin is usually taken twice daily with meals. Follow your doctor's instructions.
Metformin and sitagliptin is only part of a complete program of treatment that also includes diet, exercise, weight control, and possibly other medications. It is important to use this medicine regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.
To be sure this medication is helping your condition, your blood will need to be tested on a regular basis. Your kidney function may also need to be tested. It is important that you not miss any scheduled visits to your doctor.
Your medication needs may change if you become sick or injured, if you have a serious infection, or if you have any type of surgery. Your doctor may want you to stop taking metformin and sitagliptin for a short time if any of these situations affect you.
Take care not to let your blood sugar get too low, causing hypoglycemia. You may have hypoglycemia if you skip a meal, exercise too long, drink alcohol, or are under stress.Know the signs of low blood sugar (hypoglycemia) and how to recognize them:
hunger, headache, confusion, irritability;
drowsiness, weakness, dizziness, tremors;
sweating, fast heartbeat;
seizure (convulsions); or
fainting, coma (severe hypoglycemia can be fatal).
Always keep a source of sugar available in case you have symptoms of low blood sugar. Sugar sources include orange juice, glucose gel, candy, or milk. If you have severe hypoglycemia and cannot eat or drink, use an injection of glucagon. Your doctor can give you a prescription for a glucagon emergency injection kit and tell you how to give the injection.
Your doctor may have you take extra vitamin B12 while you are taking metformin and sitagliptin. Take only the amount of vitamin B12 that your doctor has prescribed.
Store metformin and sitagliptin at room temperature away from moisture, heat, and light.
See also: Metformin and sitagliptin dosage in more detail
Take the missed dose as soon as you remember (be sure to take the medicine with food if your doctor has instructed you to). If it is almost time for your next dose, skip the missed dose and take the medicine at the next regularly scheduled time. Do not take extra medicine to make up the missed dose.
Call your doctor at once if you have any of these serious side effects:
pancreatitis - severe pain in your upper stomach spreading to your back, nausea and vomiting, loss of appetite, fast heart rate;
feeling short of breath, even with mild exertion;
swelling or rapid weight gain;
fever, chills, body aches, flu symptoms; or
a severe blistering, peeling, and red skin rash.
Less serious side effects may include:
runny or stuffy nose, sore throat;
headache, weakness; or
mild nausea, vomiting, diarrhea, gas, stomach pain.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Usual Adult Dose for Diabetes Mellitus Type II:
The starting dose of metformin-sitagliptin should be individualized based on the patient's current regimen. For patients not adequately controlled on metformin alone, the usual starting dose of metformin-sitagliptin should be equal to 100 mg total daily dose (50 mg twice daily) of sitagliptin plus the dose of metformin already being taken. For patients taking metformin 850 mg twice daily, the recommended starting dose of metformin-sitagliptin is 50 mg sitagliptin/1000 mg metformin hydrochloride twice daily.For patients not adequately controlled on sitagliptin alone, the usual starting dose of metformin-sitagliptin is 50 mg sitagliptin/500 mg metformin hydrochloride twice daily. Patients may be titrated up to 50 mg sitagliptin/1000 mg metformin hydrochloride twice daily. Patients taking sitagliptin monotherapy with the dose adjusted for renal insufficiency should not be switched to metformin-sitagliptin.For patients switching from sitagliptin administrated with metformin, metformin-sitagliptin may be initiated at the dose of sitagliptin and metformin already being taken.Metformin-sitagliptin should be given twice daily with meals, with gradual dose escalation, to reduce the gastrointestinal (GI) side effects due to metformin.
You may be more likely to have hyperglycemia (high blood sugar) if you are taking metformin and sitagliptin with other drugs that raise blood sugar. Drugs that can raise blood sugar include:
diuretics (water pills);
steroids (prednisone and others);
phenothiazines (Compazine and others);
thyroid medicine (Synthroid and others);
birth control pills and other hormones;
seizure medicines (Dilantin and others); and
diet pills, or medicines to treat asthma, colds or allergies.
You may be more likely to have hypoglycemia (low blood sugar) if you are taking metformin and sitagliptin with other drugs that lower blood sugar. Drugs that can lower blood sugar include:
aspirin or other salicylates (including Pepto-Bismol);
sulfa drugs (Bactrim and others);
a monoamine oxidase inhibitor (MAOI);
Some medications may interact with metformin and sitagliptin. Tell your doctor if you are using any of the following drugs:
amiloride (Midamor) or triamterene (Dyrenium);
cimetidine (Tagamet) or ranitidine (Zantac);
morphine (MS Contin, Kadian, Oramorph);
nifedipine (Adalat, Procardia);
procainamide (Procan, Pronestyl, Procanbid);
quinidine (Cardioquin, Quinidex, Quinaglute);
trimethoprim (Proloprim, Primsol, Bactrim, Cotrim, Septra); or
vancomycin (Vancocin, Lyphocin).
This list is not complete and there may be other drugs that can interact with metformin and sitagliptin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.