If you have type 2 diabetes, your doctor might suggest Synjardy (empagliflozin/metformin) as a treatment option for you.

Synjardy is a prescription medication used in adults with type 2 diabetes to:

Synjardy is meant to be used on a long-term basis. It comes as tablets that you take by mouth every day. Two forms of the drug are available:

  • Synjardy. These are immediate-release tablets that you take twice per day. (“Immediate-release” means the drug is released into your body right away.)
  • Synjardy XR. These are extended-release tablets that you take once per day. (“Extended-release” means the drug is released into your body slowly over a period of time.)

For more information about Synjardy, see this in-depth article on the drug.

Like other drugs, Synjardy can sometimes cause mild or serious side effects. Keep reading to learn more.

Some people may experience mild or serious side effects during their Synjardy treatment. And some side effects are more common than others. Examples of Synjardy’s most commonly reported side effects include:

Although these are some of the most commonly reported side effects, it doesn’t mean that everyone taking Synjardy will experience them. Read on to learn more about the mild and serious side effects of Synjardy.

* To learn more about this side effect, see “Side effects explained” below.

Examples of mild side effects that have been reported with Synjardy include:

* To learn more about this side effect, see “Side effects explained” below.

In most cases, these side effects should be temporary. Some may be easily managed, too. But if you have any symptoms that are ongoing or that bother you, talk with your doctor or pharmacist. And do not stop using Synjardy unless your doctor recommends it.

Synjardy may cause mild side effects other than those listed above. See the Synjardy medication guide for details.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Synjardy, visit MedWatch.

Serious side effects that have been reported with Synjardy include:

If you develop serious side effects while taking Synjardy, call your doctor right away. If the side effects seem life threatening or if you think you’re having a medical emergency, immediately call 911 or your local emergency number.

* Synjardy and Synjardy XR have a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effects explained” section below.
† To learn more about this side effect, see “Side effects explained” below.
‡ An allergic reaction is possible after using Synjardy. But it’s not clear whether this side effect occurred in studies.

Here are the answers to some frequently asked questions about Synjardy’s side effects.

My doctor recommends I take Synjardy 12.5 mg/1,000 mg. Do I have a higher risk for side effects with this dose?

It’s possible. As with many drugs, higher doses of Synjardy may slightly raise your risk for side effects.

Synjardy 12.5 mg/1,000 mg contains 12.5 mg of empagliflozin and 1,000 mg of metformin. This is the highest strength of Synjardy tablet that’s available. It’s taken twice per day, and it’s prescribed for people who need the maximum recommended dosage of empagliflozin and metformin (25 mg of empagliflozin and 2,000 mg of metformin per day).

Synjardy XR 12.5 mg/1,000 mg also contains 12.5 mg empagliflozin and 1,000 mg metformin. But Synjardy XR tablets are only taken once per day, so this strength of Synjardy XR doesn’t contain the maximum dose. A higher strength of Synjardy XR is also available for people who need the maximum recommended dosage of empagliflozin and metformin in a form taken once daily.

The dosage of Synjardy your doctor prescribes will be based on the dosage of metformin, empagliflozin, or both medications that you’re already taking. Your doctor will also take into account how well this dosage is working for you and any side effects you may have.

If you’re concerned about side effects with the dosage of Synjardy that you’ve been prescribed, talk with your doctor or pharmacist.

Can Synjardy cause sexual side effects in females?

No, Synjardy isn’t known to cause sexual side effects in females.* This type of side effect wasn’t reported by females in studies.

However, Synjardy can sometimes cause genital yeast infections in both females and males.* Symptoms can include soreness and itching that affect the genitals, and these could make having sex uncomfortable or painful.

If you have these symptoms, ask your doctor or pharmacist to recommend a suitable antifungal treatment. And if you have a yeast infection, you should avoid having sex until it clears up. Yeast infections can be easily transmitted to your sexual partner.

Synjardy can also cause a rare but serious side effect called Fournier’s gangrene, which affects the tissue around the genital area. Symptoms of Fournier’s gangrene can include pain, redness or discoloration, swelling, or tenderness near your genitals or rectum.

Fournier’s gangrene can be life threatening, so it’s important to call your doctor or get emergency medical help right away if you have symptoms of this condition.

To learn more about these genital infections, see “Side effects explained” below.

* In this article, we use the terms “female” and “male” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, see this article.

How do the side effects of Synjardy and Synjardy XR compare?

Synjardy and Synjardy XR contain the same active drugs, empagliflozin and metformin. And they can both cause the same side effects described in the sections above.

However, Synjardy XR is an extended-release tablet that releases the active drugs slowly as it passes through your digestive system. Because of this, digestive side effects may be less common with Synjardy XR than with Synjardy. Examples of these side effects include diarrhea, nausea, vomiting, indigestion (upset stomach), flatulence (gas), and abdominal (belly) discomfort.

If you’re concerned about the risk of side effects with the form of Synjardy you’ve been prescribed, talk with your doctor or pharmacist.

How long do Synjardy’s side effects last?

Most of Synjardy’s mild side effects get better on their own in a few days or within a couple of weeks. But certain mild side effects, such as urinary tract infection (UTI) or genital yeast infection, may need to be treated with medication. These also typically get better in a few days to a couple of weeks with treatment.

Most serious side effects also get better quickly with medical treatment.

If you’re concerned about how long certain side effects of Synjardy may last, talk with your doctor or pharmacist.

How can I prevent UTIs with Synjardy?

Urinary tract infections (UTIs) are a common side effect of Synjardy, especially in females.*

To help prevent UTIs, be sure to drink plenty of water and urinate often while taking Synjardy. Keeping hydrated is also important to help prevent other serious side effects of Synjardy, such as lactic acidosis. To learn more about these side effects, see “Side effects explained” below.

Other things you can do to help prevent UTIs include:

  • keeping your genital area clean
  • taking showers instead of baths
  • wiping from front to back after urinating or a bowel movement
  • urinating shortly after sex
  • avoid using perfumed products on your genitals
  • wearing cotton underwear and loose-fitting clothing

If you do get symptoms of a UTI while taking Synjardy, see your doctor. They may need to prescribe antibiotics to treat it. Symptoms of a UTI can include:

  • pain or a burning sensation while urinating
  • urinating more often than usual
  • dark, cloudy, or strong-smelling urine
  • pain in your pelvis or the sides of your back
  • fever

If a UTI isn’t treated, it can develop into a more serious infection, such as a kidney infection or an infection that moves into the blood. These infections may need to be treated in a hospital.

* In this article, we use the term “female” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, see this article.

Synjardy comes with several warnings.

Boxed warning: Lactic acidosis

Synjardy and Synjardy XR have a boxed warning for lactic acidosis. A boxed warning is the most serious warning from the Food and Drug Administration (FDA).

To learn more, see the “Side effects explained” section below.

Other warnings

Synjardy may not be right for you if you have certain medical conditions or other factors that affect your health. Talk with your doctor about your health history before you take Synjardy. The list below includes factors to consider.

Allergic reaction. If you’ve had an allergic reaction to Synjardy or any of its ingredients, you should not take Synjardy. Ask your doctor what other medications are better options for you.

Metabolic acidosis. With metabolic acidosis, your blood becomes too acidic. Synjardy can cause lactic acidosis and ketoacidosis, which can worsen metabolic acidosis. If you have acute or chronic metabolic acidosis, you should not take Synjardy. Ask your doctor about other medications that might be better for you.

Older age. If you’re ages 65 years or older, you may have a higher risk for certain serious side effects with Synjardy, including lactic acidosis and low blood pressure. If you’re ages 65 years or older, talk with your doctor about whether Synjardy is right for you. If you do take Synjardy, your doctor may prescribe a lower dosage.

Kidney problems. If you have kidney problems, you may have a higher risk for certain serious side effects with Synjardy, including lactic acidosis and low blood pressure. Your doctor will check your kidney function before you start Synjardy and during your treatment. If you have kidney problems, your doctor may prescribe a lower dosage of Synjardy. But if you have severe kidney problems, you may not be able to take this drug.

Liver problems. If you have liver problems, you may have a higher risk for lactic acidosis with Synjardy. Talk with your doctor about whether Synjardy is right for you.

Genital yeast infections. Synjardy can increase the risk of genital yeast infections.If you have long-term or recurring genital yeast infections, you may have a higher risk for this side effect. Talk with your doctor about whether Synjardy is right for you.

Pancreatitis or pancreatic surgery. If you’ve had pancreatitis in the past or have had surgery on your pancreas, you may have a higher risk for ketoacidosis during your Synjardy treatment. Ask your doctor if Synjardy is right for you.

Alcohol use and Synjardy

You should not drink large amounts of alcohol while taking Synjardy. Doing so can raise your risk for low blood sugar. It can also raise your risk for lactic acidosis* and ketoacidosis, which are serious side effects of the drug. See the “Side effects explained” section below to read more about these side effects.

If you drink alcohol, ask your doctor how much may be safe to drink while you’re taking Synjardy.

* Synjardy and Synjardy XR have a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effects explained” section below.

Pregnancy and breastfeeding while taking Synjardy

Synjardy isn’t recommended for use during the second and third trimesters of pregnancy.

If you’re pregnant or planning to become pregnant, talk with your doctor about the possible risks of taking Synjardy. They can help you decide on the best option for you.

Synjardy may pass into breast milk, so it’s not recommended while breastfeeding. If you’re breastfeeding or planning to breastfeed, talk with your doctor about your options.

Learn more about some of the side effects Synjardy may cause.

Lactic acidosis

Taking Synjardy can cause a rare but serious side effect called lactic acidosis. Synjardy and Synjardy XR both have a boxed warning for this side effect. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). It alerts doctors and patients about drug effects that may be dangerous.

Lactic acidosis is a life threatening medical emergency that needs to be treated in a hospital. It occurs because of a buildup of lactic acid in your blood. This can be caused by metformin, which is one of the active drugs in Synjardy.

Symptoms of lactic acidosis can include:

  • sleepiness
  • weakness
  • feeling generally unwell
  • muscle pain
  • abdominal (belly) pain
  • nausea, vomiting, and diarrhea
  • trouble breathing
  • feeling cold, especially in your arms and legs
  • slow or irregular heart rate

Certain factors can increase your risk for lactic acidosis with Synjardy. These include:

  • being ages 65 years or older
  • kidney or liver problems
  • dehydration (low fluid levels)
  • having food or fluid restrictions, such as before surgery
  • drinking large amounts of alcohol
  • taking certain other medications
  • having certain X-rays where you’re given injections of dyes or contrast agents

What might help

Your doctor will determine your risk for lactic acidosis before prescribing Synjardy.

To reduce your risk for lactic acidosis, be sure to drink plenty of fluids to avoid getting dehydrated during your Synjardy treatment. This is especially important in certain situations, such as in hot weather, when doing strenuous exercise, or if you have diarrhea or vomiting. And during your treatment, you should avoid drinking large amounts of alcohol.

If you have questions about the amount of fluid you should be drinking while taking Synjardy, talk with your doctor.

Tell your doctor right away if you’re drinking less fluids than usual (such as due to fasting or illness) or if you have vomiting or diarrhea. They can recommend what to do in these situations.

You should also talk with your doctor if you have any upcoming surgeries, X-rays, or other procedures. Your doctor might want you to stop taking Synjardy temporarily.

If you have symptoms of lactic acidosis, stop taking Synjardy and call your doctor right away. But if your symptoms feel life threatening, call 911 or your local emergency number.

Genital yeast infections

Taking Synjardy can increase your risk for genital yeast infections (also known as thrush). This side effect occurs more often in females* than in males*. In fact, female genital yeast infection was one of the most common side effects reported in studies of Synjardy.

Symptoms of genital yeast infections in females can include:

  • irritation, burning, itching, or soreness in and around the vagina
  • thick, white vaginal discharge that doesn’t usually smell
  • vaginal burning, stinging, or soreness during sex or urination

Symptoms of genital yeast infections in males can include:

  • redness, irritation, and burning around the head of the penis and under the foreskin
  • thick, white discharge from the penis
  • unpleasant smell
  • trouble pulling back the foreskin (if uncircumcised)

You may have a higher risk for this side effect if you’ve had long-term or recurring genital yeast infections in the past.

* In this article, we use the terms “male” and “female” to refer to someone’s sex assigned at birth. For information about the difference between sex and gender, see this article.

What might help

If you have symptoms of a genital yeast infection, talk with your doctor or pharmacist. They can recommend a suitable treatment. For example, the following treatments are available over the counter:

  • clotrimazole cream
  • Trivagizole 3 (clotrimazole vaginal cream)
  • Monistat (miconazole cream or pessaries)

Other treatments that your doctor can prescribe include:

  • Diflucan (fluconazole tablet)
  • Gynazole-1 (butoconazole vaginal cream)
  • terconazole cream or pessaries

If you frequently get yeast infections, talk with your doctor about taking a regular antifungal medication to help prevent these infections.

Ketoacidosis

Synjardy can cause a serious side effect called ketoacidosis (when your blood becomes too acidic). This side effect wasn’t common in studies. But if it occurs, it’s a life threatening medical emergency that needs to be treated in a hospital.

Ketoacidosis occurs because of a buildup of ketones (a type of protein) in your blood. This can be caused by empagliflozin, which is one of the active drugs in Synjardy.

Symptoms of ketoacidosis can include:

  • nausea and vomiting
  • abdominal (belly) pain
  • shortness of breath
  • fruity-smelling breath
  • tiredness
  • feeling generally unwell

Certain factors can increase your risk for ketoacidosis. These include:

  • if you currently have pancreatitis (swelling or damage in your pancreas) or have had it in the past
  • drinking large amounts of alcohol
  • high fever
  • skipping meals or not eating enough
  • having surgery

What might help

To reduce your risk for ketoacidosis, you should avoid drinking large amounts of alcohol while taking Synjardy.

Tell your doctor right away if you have a fever or if you’re eating less than usual, such as due to fasting or illness. They can give advice on what to do in these situations.

You should also talk with your doctor if you’re planning to have surgery. Your doctor might want you to stop taking Synjardy temporarily.

If you have symptoms of ketoacidosis, stop taking Synjardy and call your doctor right away. But if your symptoms feel life threatening, call 911 or your local emergency number.

Fournier’s gangrene

In rare cases, Synjardy may cause a serious side effect called Fournier’s gangrene. This is a life threatening bacterial infection of the tissue between the anus and the genitals.

Fournier’s gangrene wasn’t reported in studies of Synjardy, but cases have been reported since the drug was released onto the market.

Fournier’s gangrene can cause symptoms such as:

  • pain, tenderness, redness, or swelling in the genital area
  • fever
  • feeling generally unwell

This infection can kill the layer of tissue under your skin. It can also spread into the bloodstream and can lead to death.

What might help

If you have symptoms of Fournier’s gangrene, see your doctor, or get emergency medical help right away. You’ll need to be treated in the hospital, which may include strong antibiotics and surgery to remove the damaged tissue.

If you’re concerned about your risk for this side effect with Synjardy, talk with your doctor.

Allergic reaction

Like most drugs, Synjardy can cause an allergic reaction in some people. But it’s not clear whether this side effect occurred in studies.

Symptoms can be mild or serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest an over-the-counter oral antihistamine, such as Benadryl (diphenhydramine), or a topical product, such as hydrocortisone cream, to manage your symptoms.

If your doctor confirms you had a mild allergic reaction to Synjardy, they’ll decide if you should continue using it.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you had a serious allergic reaction to Synjardy, they may have you switch to a different treatment.

Keeping track of side effects

During your Synjardy treatment, consider keeping notes on any side effects you’re having. Then, you can share this information with your doctor. This is especially helpful to do when you first start taking new drugs or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of drug you were taking when you had the side effect
  • how soon after starting that dose you had the side effect
  • what your symptoms were from the side effect
  • how it affected your daily activities
  • what other medications you were also taking
  • any other information you feel is important

Keeping notes and sharing them with your doctor will help your doctor learn more about how this drug affects you. And your doctor can use this information to adjust your treatment plan if needed.

Synjardy is an effective treatment option for adults with type 2 diabetes. Most side effects of the drug are mild, but serious side effects are also possible.

If you have questions about the possible side effects of Synjardy, talk with your doctor. They can help you decide if this drug may be a good option for you.

Examples of questions that you might want to ask your doctor include:

  • Do I have a high risk for lactic acidosis with Synjardy?
  • Do I have a high risk for genital or urinary infections with Synjardy, and how can I prevent these?
  • Do I need to stop taking Synjardy before my upcoming surgery, procedure, or X-ray?
  • If I have side effects with Synjardy, is it possible to adjust my dose?

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Disclaimer: Healthline 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.