Janumet and Janumet XR are brand-name prescription drugs. They’re FDA-approved for use in adults with type 2 diabetes. Janumet and Janumet XR are taken to help manage blood sugar levels, in combination with diet and exercise.
Janumet and Janumet XR have limitations of use. For more information, see the “Janumet and Janumet XR for diabetes” section below.
Drug details
Janumet and Janumet XR contain the active ingredients sitagliptin and metformin. Sitagliptin belongs to a class of drugs called dipeptidyl peptidase-4 inhibitors. Metformin belongs to a class of drugs called biguanides.
Janumet vs. Janumet XR
Janumet and Janumet XR come as oral tablets. They differ in the way they release the active drug:
- Janumet is an immediate-release (IR) medication. This means the tablet is fast-acting and releases the drug into your body right away.
- Janumet XR is an extended-release (ER) medication. This means the tablet is long-acting and releases the drug slowly into your body over time.
Janumet is usually taken twice daily, while Janumet XR is typically taken once daily.
Each drug is available in different strengths.
Janumet comes in two strengths:
- 50 milligrams (mg) sitagliptin/500 mg metformin
- 50 mg sitagliptin/1,000 mg metformin
Janumet XR is available in three strengths:
- 50 mg sitagliptin/500 mg metformin
- 50 mg sitagliptin/1,000 mg metformin
- 100 mg sitagliptin/1,000 mg metformin
Effectiveness
For information about the effectiveness of Janumet and Janumet XR, see the “Janumet and Janumet XR for diabetes” section below.
Janumet and Janumet XR contain the active ingredients sitagliptin and metformin. Janumet and Janumet XR are available only as brand-name medications. They’re not currently available in generic form.
Sitagliptin and metformin are available separately as generic medications. However, they aren’t available together as a combination generic drug.
A generic drug is an exact copy of the active ingredient in a brand-name medication. Generics usually cost less than brand-name drugs.
Janumet and Janumet XR can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking Janumet or Janumet XR. These lists do not include all possible side effects.
For more information about the possible side effects of Janumet or Janumet XR, talk with your doctor or pharmacist. They can give you tips on managing any side effects that may be concerning or bothersome.
Note: The Food and Drug Administration (FDA) tracks side effects of drugs it has approved. If you would like to notify the FDA about a side effect you’ve had with Janumet or Janumet XR, you can do so through MedWatch.
Mild side effects
Mild side effects* of Janumet and Janumet XR can include:
- problems with digestion, such as diarrhea, nausea and vomiting, and abdominal pain
- upper respiratory infection, such as the common cold
- headache
- low vitamin B12 level
Most of these side effects may go away within a few days or a couple of weeks. However, if they become more severe or don’t go away, talk with your doctor or pharmacist.
* This is a partial list of mild side effects from Janumet and Janumet XR. To learn about other mild side effects, talk with your doctor or pharmacist or view the prescribing information for Janumet and Janumet XR.
Serious side effects
Serious side effects from Janumet and Janumet XR aren’t common, but they can occur. Call your doctor right away if you have serious side effects. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.
Serious side effects and their symptoms can include:
- Bullous pemphigoid (a rare but possibly severe skin reaction).* Symptoms can include:
- painful blisters on certain areas of the body, such as the palms of the hands, abdomen, groin, and the soles of the feet
- itching
- redness or discoloration around the affected area
- Hypoglycemia (low blood sugar).** Symptoms can include:
- dizziness
- sweating
- Pancreatitis (inflammation of the pancreas).* Symptoms can include:
- diarrhea, nausea, or vomiting
- Severe joint pain.* Symptoms can include:
- swelling, tenderness, and stiffness around the affected joint
- Lactic acidosis (dangerous buildup of lactic acid in your body).†
- Allergic reaction.‡
- Heart problems.‡
- Kidney issues.‡
* This side effect wasn’t reported in clinical trials of Janumet and Janumet XR. It was reported after the drugs became available for use.
** The risk of low blood sugar with Janumet and Janumet XR is higher when the drugs are taken with certain other diabetes medications. For details, see the “Janumet and Janumet XR interactions” section below.
† Janumet and Janumet XR have a
‡ For more information about this side effect, see “Side effect details” below.
Side effect details
Here’s some information on certain side effects this drug may cause.
Lactic acidosis
Lactic acidosis is a possible side effect of Janumet and Janumet XR. In rare cases, this side effect can be fatal. With lactic acidosis, there’s a dangerous buildup of lactic acid in your body. This condition is a serious medical emergency that requires immediate treatment.
Due to this risk, Janumet and Janumet XR have a
Lactic acidosis wasn’t reported as a side effect in clinical trials of Janumet and Janumet XR. However, there have been reports of lactic acidosis since metformin became available for use. (Metformin is one of the active ingredients in Janumet and Janumet XR.)
You may have a higher risk of lactic acidosis with Janumet and Janumet XR if you have certain conditions. These include kidney and liver problems. Your risk may also be higher if you drink large amounts of alcohol or if you’re age 65 years or older.
Symptoms of lactic acidosis include:
- nausea and vomiting
- muscle pain
- abdominal pain
- weakness
- trouble breathing
- dizziness
If you have symptoms of lactic acidosis, stop taking Janumet and Janumet XR and call your doctor immediately. However, if your symptoms feel life threatening, you should call 911 or your local emergency number right away.
Heart problems
Heart problems are possible with Janumet and Janumet XR. This side effect wasn’t reported in clinical trials of Janumet and Janumet XR. However, there have been reports of certain heart problems in studies of other dipeptidyl peptidase-4 (DPP-4) inhibitors. (Sitagliptin, one of the active ingredients in Janumet and Janumet XR, is a DPP-4 inhibitor.)
Specifically, heart failure has been reported in studies of other DPP-4 inhibitors. Symptoms of heart failure can include:
Be sure to tell your doctor if you have heart failure before starting treatment with Janumet or Janumet XR. These drugs may worsen your condition. Your doctor can advise if it’s safe for you to take Janumet or Janumet XR.
Tell your doctor right away if you have symptoms of heart failure while taking Janumet or Janumet XR. They’ll likely prescribe a different drug to treat your condition.
Kidney issues
Taking Janumet and Janumet XR may cause kidney issues, such as kidney failure. Kidney issues weren’t reported as side effects in clinical trials of Janumet and Janumet XR. However, this side effect has been reported since the drugs became available for use.
Symptoms of kidney issues may include:
- drowsiness
- nausea
- swelling of your feet or ankles
- urinating a lesser amount than usual
- shortness of breath
- confusion
Your doctor will give you kidney function tests before you start treatment with Janumet or Janumet XR. And they’ll likely check your kidney function throughout your treatment with the drug.
Keep in mind that kidney problems can raise your risk of lactic acidosis* as a side effect of Janumet or Janumet XR. (With lactic acidosis, there’s a dangerous buildup of lactic acid in your body.) Due to this risk, it’s important to tell your doctor if you have any symptoms of kidney issues while taking Janumet or Janumet XR.
If you develop kidney issues while taking Janumet or Janumet XR, your doctor will likely have you stop taking the drug. They may prescribe a different treatment for your condition.
* Janumet and Janumet XR have a
Allergic reactionAs with most drugs, Janumet and Janumet XR may cause allergic reaction in some people. This side effect wasn’t reported in clinical trials of Janumet and Janumet XR. However, allergic reaction has been reported in people taking sitagliptin after it became available for use. (Sitagliptin is one of the active ingredients in Janumet and Janumet XR.)
Symptoms of a mild allergic reaction can include:
A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include:
- swelling under your skin, typically in your eyelids, lips, hands, or feet
- swelling of your tongue, mouth, or throat
- trouble breathing
Call your doctor right away if you have an allergic reaction to Janumet or Janumet XR, as the reaction could become severe. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.
The Janumet or Janumet XR dosage your doctor prescribes will depend on several factors. These include:
- your age
- other medical conditions you may have
- other diabetes medications you may be taking
Typically, your doctor will start you on a low dosage. Then, they’ll adjust it over time to reach the amount that’s right for you. Your doctor will ultimately prescribe the smallest dosage that provides the desired effect.
The following information describes dosages that are commonly taken or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.
Drug forms and strengths
Janumet and Janumet XR come as oral tablets. They differ in the way they release the active drug:
- Janumet is an immediate-release (IR) medication. This means the tablet is fast-acting and releases the drug into your body right away.
- Janumet XR is an extended-release (ER) medication. This means the tablet is long-acting and releases the drug slowly into your body over time.
Janumet strengths: 50 mg/500 mg and 50 mg/1,000 mg
Janumet comes in two strengths:
- 50 milligrams (mg) sitagliptin/500 mg metformin IR
- 50 mg sitagliptin/1,000 mg metformin IR
Janumet XR strengths: 50 mg/500 mg, 50 mg/1,000 mg, and 100 mg/1,000 mg
Janumet XR is available in three strengths:
- 50 mg sitagliptin/500 mg metformin ER
- 50 mg sitagliptin/1,000 mg metformin ER
- 100 mg sitagliptin/1,000 mg metformin ER
Dosage for type 2 diabetes
For type 2 diabetes, the usual starting dosage of Janumet and Janumet XR depends on whether you’re already taking metformin. Metformin is a commonly prescribed drug for type 2 diabetes. It’s also one of the active ingredients in Janumet and Janumet XR.
The table below provides the typical starting dosages of Janumet and Janumet XR:
| Starting dosage of Janumet | Starting dosage of Janumet XR | |
| Not already taking metformin | 50 mg sitagliptin/500 mg metformin twice daily | 100 mg sitagliptin/1,000 mg metformin once daily |
| Already taking metformin | 50 mg sitagliptin/1,000 mg metformin* twice daily | 100 mg sitagliptin/2,000 mg metformin† once daily |
* This is the recommended dosage for people already taking metformin 850 mg twice daily.
† This is the recommended dosage for people already taking metformin 850 mg or 1,000 mg twice daily.
Your doctor may slowly increase your dosage of Janumet or Janumet XR until you’ve reached your target blood sugar level. The maximum dose is the same for both Janumet and Janumet XR: 100 mg sitagliptin and 2,000 mg metformin.
What if I miss a dose?
If you miss a dose of Janumet or Janumet XR, take your missed dose as soon as you remember. However, if it’s almost time for your next dose, just skip it. Then, take your next dose again on your regular schedule. If you aren’t sure whether to take a missed dose or skip it, talk with your doctor or pharmacist.
Do not take any extra doses of Janumet or Janumet XR to make up for a missed dose. Doing this can raise your risk of side effects. (For information about the drugs’ side effects, see the “Janumet and Janumet XR side effects” section above.)
To help make sure you don’t miss a dose, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.
Will I need to take this drug long term?
Janumet and Janumet XR are meant to be taken as long-term treatments. If you and your doctor determine that Janumet or Janumet XR is safe and effective for you, you’ll likely take it long term.
As with all medications, the cost of Janumet and Janumet XR can vary. The drug’s cost may vary based on the strength you’re taking. For instance, the price of Janumet 50 milligrams (mg)/1,000 mg may differ from that of Janumet 50 mg/500 mg. The actual price you’ll pay depends on your insurance plan, your location, and the pharmacy you use.
Keep in mind that you may be able to get a 90-day supply of Janumet or Janumet XR. If approved by your insurance company, getting a 90-day supply of the drug could reduce your number of trips to the pharmacy and help lower the cost. If you’re interested in this option, check with your doctor, pharmacist, or insurance company.
Before approving coverage for Janumet or Janumet XR, your insurance company may require you to get prior authorization. This means your doctor and insurance company will need to communicate about your prescription before the insurance company will cover the drug. The insurance company will review the prior authorization request and decide if the drug will be covered.
If you’re not sure if you’ll need to get prior authorization for Janumet or Janumet XR, contact your insurance company.
Financial and insurance assistance
If you need financial support to pay for Janumet or Janumet XR, or if you need help understanding your insurance coverage, help is available.
Merck & Company, Inc., the manufacturer of Janumet and Janumet XR, offers a coupon to help lower the cost of these drugs. For more information and to find out if you’re eligible for support, visit the manufacturer’s website.
To learn more about saving money on prescriptions, check out this article.
Mail-order pharmacies
Janumet and Janumet XR may be available through a mail-order pharmacy. Using this service may help lower the drug’s cost and allow you to get your medication without leaving home.
If recommended by your doctor, you may be able to receive a 90-day supply of Janumet or Janumet XR, so there’s less concern about running out of the medication. If you’re interested in this option, check with your doctor, pharmacist, or insurance company. Some Medicare plans may help cover the cost of mail-order medications.
If you don’t have insurance, you can ask your doctor or pharmacist about online pharmacy options.
Generic version
Janumet and Janumet XR contain the active ingredients sitagliptin and metformin. Janumet and Janumet XR are available only as brand-name medications. They’re not currently available in generic form.
Sitagliptin and metformin are available separately as generic medications. However, they aren’t available together as a combination generic drug.
A generic drug is an exact copy of the active ingredient in a brand-name medication. Generics usually cost less than brand-name drugs.
Other drugs are available that can treat type 2 diabetes. Some may be a better fit for you than others. If you’re interested in finding an alternative to Janumet or Janumet XR, talk with your doctor. They can tell you about other medications that may work well for you.
Examples of other drugs that may be taken to treat type 2 diabetes include:
- dipeptidyl peptidase-4 inhibitors, such as:
- sitagliptin (Januvia)
- saxagliptin (Onglyza)
- linagliptin (Tradjenta)
- sulfonylureas, such as:
- glyburide (Glynase, Diabeta)
- glipizide (Glucotrol)
- glimepiride (Amaryl)
- sodium glucose cotransporter 2 inhibitors, such as:
- glucagon-like peptide-1 agonists, such as:
- thiazolidinediones, such as:
- rosiglitazone (Avandia)
- pioglitazone (Actos)
- biguanides, such as metformin (Fortamet, Glumetza, Riomet)
- combination drugs, such as:
- linagliptin/metformin (Jentadueto)
- dapagliflozin/metformin (Xigduo)
- canagliflozin/metformin (Invokamet)
The Food and Drug Administration (FDA) approves prescription drugs such as Janumet and Janumet XR to treat certain conditions.
Janumet and Janumet XR for type 2 diabetes
Janumet and Janumet XR are FDA-approved for use in adults with type 2 diabetes. The drugs are taken to help manage blood sugar levels in combination with diet and exercise.
About type 2 diabetes
With type 2 diabetes, your body becomes resistant to the effects of a hormone called insulin. Insulin helps your body process sugar by moving it from your blood into your cells.
Insulin resistance means your body still makes insulin, but it doesn’t process sugar as well as it should. This can lead to high blood sugar. Over time, high blood sugar can damage your eyes, heart, kidneys, and nerves.
Symptoms of type 2 diabetes include:
- urinating more often than usual
- blurry vision
- fatigue
- increased thirst or hunger
You can learn more about diabetes by visiting Medical News Today’s diabetes hub.
Limitations of use
It’s important to note that Janumet and Janumet XR should not be taken to treat type 1 diabetes.
It also isn’t known if Janumet and Janumet XR are safe for people with a history of pancreatitis (inflammation of the pancreas). The drugs haven’t been studied in this group of people.
Effectiveness for type 2 diabetes
Janumet and Janumet XR contain the active ingredients sitagliptin and metformin. The American Diabetes Association recommends a combination of metformin and a dipeptidyl peptidase-4 inhibitor, such as sitagliptin, to treat type 2 diabetes in certain situations.* In this case, your doctor may prescribe you Janumet or Janumet XR instead of prescribing sitagliptin and metformin individually.
Janumet and Janumet XR have been found effective for managing blood sugar levels in adults with type 2 diabetes in clinical trials. For more information on how the drugs performed in these trials, see the prescribing information for Janumet and Janumet XR.
* Metformin is generally the first drug prescribed for type 2 diabetes. If metformin doesn’t lower your blood sugar levels enough on its own, your doctor may prescribe another diabetes drug to take with it. Your doctor will advise on the treatment plan that’s best for you.
Janumet and Janumet XR and children
Janumet and Janumet XR aren’t approved for use in children. It isn’t known if the drugs are safe or effective for children.
Janumet and Janumet XR are approved to treat type 2 diabetes. The drugs are taken to help manage blood sugar levels, in combination with diet and exercise.
Your doctor, nutritionist, or dietitian can help you develop a diet plan that’s best for managing your diabetes. They can also suggest different exercises that can help lower health risks related to diabetes.
To learn more about your diabetes treatment plan, talk with your doctor.
Here are answers to some frequently asked questions about Janumet and Janumet XR.
Is Janumet or Janumet XR taken for weight loss?
Janumet and Janumet XR aren’t currently approved for weight loss. The drugs are approved to treat type 2 diabetes when taken along with diet and exercise.
However, metformin (one of the active ingredients in Janumet and Janumet XR) is sometimes prescribed off-label for weight loss. (Off-label means prescribing a drug for a purpose other than what it’s been approved for by the Food and Drug Administration.)
Some people who took Janumet and Janumet XR in clinical trials lost weight. So, it’s possible that you may lose weight while taking Janumet or Janumet XR for type 2 diabetes. However, the drugs aren’t typically prescribed for this purpose.
If you have questions about weight loss while taking Janumet or Janumet XR, talk with your doctor. They can suggest a diet and exercise plan that may help you maintain a weight that’s healthy for you.
Are Janumet and Janumet XR harmful for your kidneys?
Possibly. Taking Janumet or Janumet XR may cause kidney issues, such as kidney failure. Kidney issues weren’t reported as side effects in clinical trials of Janumet and Janumet XR. However, this side effect has been reported since the drugs became available for use.
For more information, see “Kidney issues” in the “Janumet and Janumet XR side effects” section above.
Is Janumet or Janumet XR a blood thinner?
No, Janumet and Janumet XR aren’t blood thinners. Blood thinners are drugs that help prevent or treat blood clots.
Janumet and Janumet XR are approved to treat type 2 diabetes. They’re taken to help manage blood sugar levels, in combination with diet and exercise. For details, see the “How Janumet and Janumet XR work” section below.
Taking more than the recommended dosage of Janumet or Janumet XR can lead to serious side effects.
Do not take more Janumet or Janumet XR than your doctor recommends.
Overdose symptoms
Symptoms of an overdose with Janumet or Janumet XR can include:
- lactic acidosis* (dangerous buildup of lactic acid in your body)
- hypoglycemia (low blood sugar)
* Janumet and Janumet XR have a
What to do in case of overdose
If you think you’ve taken too much of this drug, call your doctor. You can also call the American Association of Poison Control Centers at 800-222-1222 or use its online tool. But if your symptoms are severe, call 911 or your local emergency number, or go to the nearest emergency room right away.
It may be best to avoid drinking large amounts of alcohol while taking Janumet or Janumet XR.
This is because drinking alcohol can raise your risk of certain side effects from the drug. These include lactic acidosis* (dangerous buildup of lactic acid in your body) and pancreatitis (inflammation of the pancreas).
Alcohol can also affect how well Janumet or Janumet XR works to manage your blood sugar levels. This is because drinking alcohol can change your blood sugar levels.
If you drink alcohol, talk with your doctor about how much is safe for you to drink while taking Janumet or Janumet XR.
* Janumet and Janumet XR have a
Janumet and Janumet XR can interact with several other medications.
Different interactions can cause different effects. For instance, some interactions can interfere with how well a drug works. Other interactions can increase the likelihood of side effects or make them more severe.
Janumet and Janumet XR and other medications
Below is a list of medications that can interact with Janumet and Janumet XR. This list does not contain all drugs that may interact with Janumet and Janumet XR.
Before taking Janumet or Janumet XR, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also, tell them about any vitamins, herbs, and supplements you take. Sharing this information can help you avoid potential interactions.
Drugs that can raise your risk of hypoglycemia
Certain drugs can raise your risk of hypoglycemia (low blood sugar) while taking Janumet or Janumet XR. Examples of these drugs include diabetes medications, such as:
- sulfonylureas, such as:
- glimepiride (Amaryl)
- glyburide (Diabeta)
- glipizide (Glucotrol)
- insulins, such as:
- insulin degludec (Tresiba)
Drugs that can raise your risk of hyperglycemia
Certain drugs can raise your risk of hyperglycemia (high blood sugar) while taking Janumet or Janumet XR. These include:
- Diuretics, which are taken to treat high blood pressure. Examples include:
- hydrochlorothiazide (Microzide)
- chlorothiazide (Diuril)
- chlorthalidone (Thalitone)
- Calcium channel blockers, which are taken to treat high blood pressure. Examples include:
- diltiazem (Cardizem CD, Cartia XT)
- amlodipine (Norvasc)
- verapamil (Calan SR, Verelan)
- Corticosteroids, which are taken to treat swelling. Examples include:
- prednisone (Rayos)
- methylprednisolone (Medrol)
- Phenothiazines, which are taken to treat mental health conditions. Examples include:
- chlorpromazine
- perphenazine
- thioridazine
- Thyroid hormones, which are taken to treat hypothyroidism (underactive thyroid). Examples include:
- levothyroxine (Levoxyl, Synthroid)
- liothyronine (Cytomel)
- Hormonal birth control. Examples include:
- ethinyl estradiol/norethindrone
- ethinyl estradiol/levonorgestrel
- drospirenone/estetrol
- Certain seizure drugs, such as phenytoin (Dilantin).
- Certain antibiotics, such as isoniazid.
- Niacin, which is taken to lower cholesterol.
Drugs that can raise your risk of side effects from Janumet or Janumet XR
Certain drugs can increase your risk of side effects from Janumet or Janumet XR. These include:
- Carbonic anhydrase inhibitors. Examples include:
- the seizure drugs topiramate (Topamax, Trokendi XR) and zonisamide (Zonegran)
- the altitude sickness drug acetazolamide
- the paralysis drug dichlorphenamide (Keveyis)
- Certain tyrosine kinase inhibitors, which are taken to treat cancer. An example is vandetanib (Caprelsa).
- Certain antianginal agents, which are used to treat angina (chest pain). An example is ranolazine (Ranexa).
- Certain integrase inhibitors, which are taken to treat HIV. An example is dolutegravir (Tivicay).
- Certain H2 blockers, which are used to treat heartburn. An example is cimetidine (Tagamet HB).
If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.
Janumet and Janumet XR and herbs and supplements
There aren’t any herbs or supplements that have been specifically reported to interact with Janumet and Janumet XR. However, you should still check with your doctor or pharmacist before taking any of these products while taking Janumet or Janumet XR.
Janumet and Janumet XR and foods
There aren’t any foods that have been specifically reported to interact with Janumet and Janumet XR. If you have any questions about eating certain foods with Janumet or Janumet XR, talk with your doctor.
You should take Janumet or Janumet XR according to the instructions your doctor gives you.
Janumet and Janumet XR come as tablets that you swallow.
When to take
If you’re prescribed Janumet, you’ll likely take it twice daily with meals. Janumet XR is taken once daily, usually with your evening meal.
To help make sure you don’t miss a dose, try using a medication reminder. This can include setting an alarm or using a timer. You could also download a reminder app on your phone.
Taking Janumet and Janumet XR with food
You’ll take Janumet or Janumet XR with a meal.
Can Janumet and Janumet XR be crushed, split, or chewed?
No, Janumet and Janumet XR should not be crushed, split, or chewed. It’s best to swallow the tablets whole.
Talk with your doctor or pharmacist if you have trouble swallowing Janumet or Janumet XR tablets.
Janumet and Janumet XR are approved to treat type 2 diabetes. The drugs are taken to help manage blood sugar levels, in combination with diet and exercise.
With type 2 diabetes, your body becomes resistant to the effects of a hormone called insulin. (Insulin resistance means your body still makes insulin, but it doesn’t process sugar as well as it should.) This can lead to high blood sugar, which can damage your heart, kidneys, eyes, and nerves.
Janumet and Janumet XR are taken to help manage blood sugar levels. They contain the active ingredients sitagliptin and metformin.
Sitagliptin belongs to a class of drugs called dipeptidyl peptidase-4 inhibitors. The drug works by increasing the amount of insulin your body makes, which helps lower your blood sugar level.
Metformin belongs to a class of drugs called biguanides. The drug works in several ways to lower blood sugar. Metformin works by:
- decreasing the amount of glucose (a type of sugar) your liver makes
- decreasing the amount of glucose your body absorbs from food
- helping your body respond better to insulin
How long does it take to work?
It may take about several weeks for your blood sugar levels to improve after you start taking Janumet or Janumet XR. Your doctor may adjust your dosage over time to make sure the drug is working for you.
How long does it stay in your system?
The half-life of Janumet and Janumet XR can be used to figure out how long the drugs stay in your system. The half-life of a drug is the amount of time it takes for half of its dose to leave your body.
The half-life of sitagliptin is about 12 hours. This means it takes about 12 hours for your body to get rid of half of a dose of sitagliptin.
The half-life of metformin varies from about 6 to 17 hours. So, it takes about 6 to 17 hours for your body to get rid of half of a dose of metformin.
In general, it usually takes about five half-lives for a drug to leave your system entirely. For sitagliptin, this means the drug will stay in your system for about 60 hours after your last dose. And for metformin, this means the drug will stay in your system for about 30 to 85 hours after your last dose.
It’s not known if Janumet or Janumet XR is safe to take while pregnant. There haven’t been enough studies of the drugs during pregnancy to know for certain.
If you’re pregnant or planning a pregnancy while taking Janumet or Janumet XR, talk with your doctor. They can advise on the risks and benefits of taking the drug while pregnant.
If you take Janumet or Janumet XR during pregnancy, consider enrolling in a
It’s unknown if Janumet or Janumet XR is safe to take during pregnancy. If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs while you’re taking Janumet or Janumet XR.
For more information about taking Janumet or Janumet XR during pregnancy, see the “Janumet and Janumet XR and pregnancy” section above.
It isn’t known if Janumet or Janumet XR is safe to take while breastfeeding. It’s unknown if the drugs pass into breast milk.
If you’re breastfeeding or planning to breastfeed, talk with your doctor about the risks and benefits of Janumet or Janumet XR before taking the drugs.
This drug comes with several precautions.
FDA warning: Lactic acidosis
This drug has a boxed warning. This is the most serious warning from the Food and Drug Administration (FDA). A
Metformin (one of the active ingredients in Janumet and Janumet XR) may cause lactic acidosis. With lactic acidosis, there’s a dangerous buildup of lactic acid in your body. This condition is a serious medical emergency that requires immediate treatment.
You may have a higher risk of lactic acidosis with Janumet or Janumet XR if you have certain conditions. These include kidney and liver problems. Your risk may also be higher if you drink large amounts of alcohol or you’re age 65 years or older.
Symptoms of lactic acidosis include muscle pain, abdominal pain, weakness, and trouble breathing. If you have symptoms of lactic acidosis, stop taking Janumet or Janumet XR and call your doctor immediately. However, if your symptoms feel life threatening, you should call 911 or your local emergency number right away.
To learn more about this boxed warning, see “Side effect details” in the “Janumet and Janumet XR side effects” section above.
Other precautions
Before taking Janumet or Janumet XR, talk with your doctor about your health history. Janumet and Janumet XR may not be right for you if you have certain medical conditions or other contraindications. A contraindication is a factor or condition that could prevent your doctor from prescribing a drug due to a risk of harm.
Factors to consider include:
- Certain imaging studies. Some people shouldn’t take Janumet or Janumet XR if they’re getting an imaging test that uses iodine contrast. (With this type of imaging test, iodine is injected into a vein before the images are taken.) Be sure to talk with your doctor before having imaging tests.
- Heart failure. Janumet and Janumet XR may cause new or worsening heart failure. Be sure to tell your doctor if you have heart failure before starting treatment. They’ll advise if it’s safe for you to take Janumet or Janumet XR.
- Low levels of vitamin B12. Be sure to tell your doctor if you have a low vitamin B12 level before you start taking Janumet or Janumet XR. The drugs can cause low vitamin B12 levels as a side effect. And your risk of this side effect may be higher if you already have low B12. Your doctor may monitor your vitamin B12 levels more closely than usual while you’re taking Janumet or Janumet XR.
- Kidney problems. If you have kidney problems, such as kidney failure, tell your doctor before starting treatment with Janumet or Janumet XR. The drugs may cause kidney problems as a side effect. Kidney problems can also raise your risk of lactic acidosis. (For more information, see “FDA warning: Lactic acidosis” right above.) Due to these risks, your doctor typically will not prescribe Janumet or Janumet XR if you already have this condition.
- Liver problems. People with liver problems may have a higher risk of lactic acidosis when taking Janumet or Janumet XR. (For more information, see “FDA warning: Lactic acidosis” right above.)
- Older age. If you’re age 65 years or older, you may have a higher risk of lactic acidosis with Janumet and Janumet XR. For more information, see “FDA warning: Lactic acidosis” right above.
- Planned surgery. If you have a planned surgery, talk with your doctor about whether you should take Janumet or Janumet XR. Some surgeries may require you to fast or follow a limited diet. If you’ll need to follow a different diet, your doctor may recommend that you temporarily stop taking Janumet or Janumet XR around the time of your surgery.
- Allergic reaction. If you’ve had an allergic reaction to Janumet or Janumet XR or any of its ingredients, your doctor will likely not prescribe you the drug. Ask your doctor which other medications are better options for you.
- Pregnancy. It’s not known if Janumet or Janumet XR is safe to take while pregnant. For more information, see the “Janumet and Janumet XR and pregnancy” section above.
- Breastfeeding. It’s unknown if Janumet or Janumet XR are safe to take while breastfeeding. To learn more, see the “Janumet and Janumet XR and breastfeeding” section above.
Note: For more information about the potential negative effects of Janumet and Janumet XR, see the “Janumet and Janumet XR side effects” section above.
When you get Janumet or Janumet XR from the pharmacy, the pharmacist will add an expiration date to the label on the bottle. This date is typically 1 year from the date they dispensed the medication.
The expiration date helps guarantee that the medication is effective during this time. The
Storage
How long a medication remains safe to take can depend on many factors, including how and where you store the medication.
Janumet and Janumet XR tablets should be stored at room temperature, which is 68°F to 77°F (20°C to 25°C). For short periods of time, such as when traveling, Janumet and Janumet XR tablets may be stored at temperatures of 59°F to 86°F (15°C to 30°C). You should keep the tablets in a tightly sealed container. Avoid storing this medication in areas where it could get damp or wet, such as bathrooms.
Disposal
If you no longer need to take Janumet or Janumet XR and have leftover medication, it’s important to dispose of it safely. This helps prevent others, including children and pets, from taking the drug by accident. It also helps keep the drug from harming the environment.
This article provides several useful tips on medication disposal. You can also ask your pharmacist for information about how to dispose of your medication.
Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.
