Janumet side effects and how to avoid them

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

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

What is Janumet?

Janumet 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 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, 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, metformin slows down the process that causes your liver to do this, lowering the amount of sugar released.

Janumet dosage

Janumet is available in tablet form in the following doses: Sitagliptin 50 mg/metformin 500 mg and sitagliptin 50 mg/metformin 1000 mg. It is also available as Janumet XR (extended-release) long-acting oral tablets.

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 side effects

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

  • 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 can cause more serious side effects, including:

  • Severe allergic reactions to the medication – 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 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 cause pancreatic cancer?

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

Does Janumet cause erectile dysfunction?

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

Does Janumet cause hair loss?

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

Does Janumet cause weight gain?

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

Does Janumet cause constipation?

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

Does Janumet cause kidney damage?

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

How long do Janumet side effects last?

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

Janumet drug interactions

Janumet 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, 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 warnings & precautions

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

  • Are allergic to the active ingredients sitagliptin or metformin
  • Are allergic to any of the other ingredients in Janumet
  • 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 if you:

  • Are taking any of the medications that could interact with Janumet (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 good for diabetes?

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

How to avoid Janumet side effects

The best way to avoid side effects is to take Janumet 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 as 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. 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 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.

7. Know the signs and symptoms of Janumet 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 you’re taking, including over-the-counter drugs, vitamins, and herbal supplements, as they can interact with Janumet.

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 as needed.

Medically reviewed

A medical professional has reviewed this article.

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Sources (3)

  1. WebMD - Janumet - Uses, Side Effects, and More

  2. Janumet official website - Janumet side effects

  3. FDA - highlights of prescribing information for Janumet

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.
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