Janumet XR side effects and how to avoid them

Janumet XR is a brand-name FDA (Food and Drug Administration) approved diabetes medication manufactured by Merck Sharp & Dohme Corp. It is used to help manage high blood sugar levels (hyperglycemia) in adults with type 2 diabetes mellitus. Janumet XR should be used alongside exercise and changes to your diet. While Janumet XR is generally well tolerated, there are some potential side effects that people should be aware of. The most common side effects of Janumet XR include upper respiratory infections. Less common but more serious side effects can include pancreatitis.

Learn more about the side effects of Janumet XR and what you can do to avoid them.

What is Janumet XR?

Janumet XR contains two active ingredients, called sitagliptin and metformin hydrochloride. These active ingredients reduce the amount of sugar released into your blood and increase the insulin produced by your pancreas. Janumet XR helps you lower your blood glucose levels.

Sitagliptin belongs to the drug class known as dipeptidyl peptidase-4/DPP-4 inhibitors, which increases the amount of insulin you produce after you’ve eaten. When you digest food, your stomach and gut produce digestive hormones called GLP-1 and GIP that make your pancreas secrete insulin. As you continue to digest your food, these digestive hormones are broken down by an enzyme called DPP-4. This allows your levels of insulin to fall again. If you take Janumet XR, sitagliptin stops the DPP-4 enzyme from breaking down these digestive hormones. This keeps the hormones active for longer and makes you produce more insulin.

Metformin is classed as a biguanide and reduces how much sugar your liver releases into your blood. As your digestive system breaks down food, your liver releases sugar into your blood. If you take Janumet XR, metformin slows down the process that causes your liver to do this, lowering the amount of sugar released.

Janumet XR dosage

Janumet XR is available in extended-release tablet form in the following doses: Sitagliptin 100 mg/metformin HCl 1000 mg, sitagliptin 50 mg/metformin HCl 500 mg, and sitagliptin 50 mg/metformin HCl 1000 mg.

You are advised to read the medication guide provided with this medicine for the drug information and patient information, and always speak with your healthcare provider for medical advice about any changes to your dose so they can monitor and evaluate your condition.

Janumet XR side effects

The most common possible side effects caused by Janumet XR in clinical trials include:

  • Headaches
  • Diarrhea
  • Nausea, vomiting
  • Back pain
  • Upset stomach
  • Loss of appetite
  • Abdominal pain
  • Upper respiratory tract infections, sore throat
  • Hypoglycemia – symptoms of low blood sugar include sweating, shaking, increased heart rate, hunger, dizziness, blurred vision, or tingling in the hands and feet

In rare instances, Janumet XR can cause more serious side effects, including:

  • Severe allergic reactions to the medication – skin rash, hives, itching, severe dizziness, trouble breathing
  • Risk of lactic acidosis – build-up of lactic acid in your body. Symptoms of lactic acidosis include breathing difficulties, shortness of breath, irregular heartbeat, tiredness, sleepiness, muscle pain, and stomach pain
  • Severe joint pain (arthralgia)
  • Anemia
  • Unusual skin blisters
  • Inflammation of the pancreas (pancreatitis)
  • Bullous pemphigoid (a rare but potentially severe skin reaction)
  • Kidney failure

If you experience any of these serious side effects, stop taking Janumet XR and seek medical attention immediately. You are encouraged to report the negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch, or call 1-800-FDA-1088.

Does Janumet XR cause pancreatic cancer?

Pancreatic cancer is not a side effect of Janumet XR. Pancreatitis (inflammation of the pancreas), however, has been reported in trials of Janumet XR and Janumet.

Does Janumet XR cause erectile dysfunction?

Erectile dysfunction is not a side effect of Janumet XR. Diabetes may, however, cause erectile dysfunction. Speak to your doctor if you experience this side effect.

Does Janumet XR cause hair loss?

Hair loss is not a side effect of Janumet XR. Diabetes may, however, cause hair loss. Speak to your doctor if you experience this side effect.

Does Janumet XR cause weight gain?

Janumet XR does not normally cause weight gain but may cause a slight weight loss.

Does Janumet XR cause constipation?

Janumet XR may cause constipation, stomach upset, and abdominal pain as common side effects.

Does Janumet XR cause kidney damage?

Janumet XR may cause kidney problems as a side effect. Speak to your doctor if you have kidney problems before starting treatment with Janumet XR.

How long do Janumet XR side effects last?

Side effects of Janumet XR may go away and not require medical attention. Speak to your doctor for medical advice if you have long-term side effects.

Janumet XR drug interactions

Janumet XR can interact with other medications, including carbonic anhydrase inhibitors (such as zonisamide, acetazolamide, or dichlorphenamide), cationic drugs (such as amiloride, digoxin, morphine, or vancomycin, diuretics, corticosteroids, estrogens, oral contraceptives, nicotinic acid, and calcium channel blocking drugs.

Before taking Janumet XR, be sure to tell your doctor about all of the medications you are taking to ensure they are safe to take at the same time.

Janumet XR warnings & precautions

Janumet XR isn’t suitable for everyone. Don’t take Janumet XR if you:

  • Are allergic to the active ingredients sitagliptin or metformin
  • Are allergic to any of the other ingredients in Janumet XR
  • Have type 1 diabetes
  • Have reduced kidney function
  • Have diabetic ketoacidosis – a potentially life-threatening condition caused by diabetes where you break down body fat too quickly
  • Are under 18 years of age

Talk to your physician before taking Janumet XR if you:

  • Are taking any of the medications that could interact with Janumet XR (listed in the section above)
  • Have a history of pancreatitis
  • Have heart problems, including congestive heart failure
  • Have vitamin B12 deficiency
  • Have liver disease or other liver problems
  • Have kidney disease
  • Are going to get an injection of dye or contrast agents for an x-ray
  • Drink alcohol often or binge drink alcohol
  • Are pregnant or are planning to get pregnant
  • Are breastfeeding or are planning to breastfeed
  • Are over 65 years of age

Is Janumet XR good for diabetes?

Janumet XR reduces blood sugar levels in adults with type 2 diabetes. Janumet XR may be taken alone or with other medications to help reduce high blood sugar levels.

What is the best time of day to take Janumet XR?

It is best to take Janumet XR with your evening meal.

Why take Janumet XR in the evening?

You are advised to take Janumet XR with your evening meal to help reduce your chance of having an upset stomach.

How to avoid Janumet XR side effects

The best way to avoid side effects is to take Janumet XR as directed by your doctor. Follow your doctor’s instructions carefully, and do not take more or less than prescribed.

If you experience any side effects, talk to your doctor or pharmacist. They may be able to recommend ways to help reduce or prevent some of the side effects.

1. Stick to the recommended dosage

Take your prescribed dose of Janumet XR recommended by your healthcare professional. Do not take more or less than prescribed.

2. Monitor your blood sugar levels

If you have diabetes, it is important to monitor your blood sugar levels closely while taking Janumet XR. Check your blood sugar levels as directed by your doctor and report any changes to your doctor immediately.

3. Drink plenty of fluids

Drink eight to 10 glasses of water or fluids every day to help prevent dehydration, which can make side effects worse.

4. Avoid alcohol

Avoid drinking alcohol while taking Janumet XR, as it can increase your risk of lactic acidosis.

5. Don’t skip meals

Eating regular meals and snacks will help to prevent low blood sugar levels (hypoglycemia).

6. Check your feet

If you have diabetes, check your feet for any cuts, sores, or redness regularly. Tell your doctor if you experience any problems with your feet while taking Janumet XR.

7. Know the signs and symptoms of Janumet XR side effects

Signs and symptoms of side effects include loss of appetite and an upset stomach. If you experience these symptoms, speak to your doctor for medical advice.

8. Tell your doctor about all medications you’re taking

Be sure to tell your doctor about all other medications, including over-the-counter drugs, vitamins, and herbal supplements, as they can interact with Janumet XR.

9. Get regular medical checkups

It is important to get regular medical checkups and monitor your medical conditions. Your doctor will monitor your side effects and may adjust your dose of Janumet XR as needed.

Medically reviewed

A medical professional has reviewed this article.

Jamie Winn, PharmD
Jamie Winn, PharmD

Jamie Winn, PharmD

Medical Writer & Reviewer

Jamie Winn, PharmD

Medical Writer & Reviewer

Dr. Jamie Winn received his Doctor of Pharmacy in 2002 from the University of South Carolina College of Pharmacy, Columbia, SC. Jamie is a medical reviewer for NiceRx.

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The content on this website is intended for information purposes only. It does not constitute medical advice. The information on this website should not be relied upon and is not a substitute for professional medical advice. You should always speak to your doctor regarding the risks and benefits of any treatment.