Key takeaways

Farxiga (dapagliflozin) is a medication for Type 2 diabetes mellitus, certain chronic kidney diseases, and congestive heart failure, working by increasing glucose elimination through urine.
Common side effects of Farxiga include urinary tract and genital yeast infections, with serious risks including kidney injury and orthostatic hypotension.
To mitigate side effects, patients should maintain hydration, monitor for urinary or genital issues, and avoid conditions that increase dehydration or ketosis risk.
Farxiga has specific contraindications, including pregnancy, breastfeeding, and children under 18, and it may interact with medications affecting kidney function or dehydration.

A brand-name diabetes medication with a novel mechanism, Farxiga (dapagliflozin) has unique benefits and side effects that are important to understand. Farxiga is a sodium-glucose cotransporter 2 (SGLT2) inhibitor, a drug class that lowers high blood sugar levels by promoting the elimination of glucose through the urine, instead of increasing insulin production or sensitivity like other oral therapies for Type 2 diabetes mellitus. Other members of the class include Jardiance and Invokana.

By inhibiting the SGLT2 channel in the kidney tubules, these medications increase urinary glucose and consequently increase urine output. This mechanism likely explains why Farxiga can have beneficial effects on kidney function in the long term and prove helpful in eliminating excess fluid volume in the body. In fact, the Food and Drug Administration (FDA) indications for Farxiga include treatment of certain chronic kidney disease and congestive heart failure patients, in addition to treatment of Type 2 diabetes mellitus. The drug’s mechanism of action is also tied to a list of noteworthy possible side effects, which this article will review in detail.

RELATED: What is Farxiga?

Common side effects of Farxiga

The following side effects were reported in more than 2% of patients taking Farxiga compared to a placebo.

Genital mycotic infections (such as vaginal yeast infection)
Nasopharyngitis (sore throat and nasal inflammation) or influenza
Urinary tract infection
Urinary frequency or discomfort
Back pain
Nausea
Constipation
Extremity pain
Elevated creatinine (blood test marker of kidney function)

Urinary tract infection

According to the manufacturer AstraZeneca’s medication guide, about 5% of individuals experience a urinary tract infection (UTI) while taking Farxiga. Burning with urination and increased frequency of urination are common UTI symptoms. Of note, however, more severe UTIs can occur and are typically heralded by fever, back pain, or vomiting. Whether mild or severe, UTI symptoms necessitate medical help.

Yeast infections

Genital yeast infections afflict about 8% of women and 3% of men on Farxiga, likely as a result of glucosuria (sugar in the urine). Vaginal yeast infections in women and yeast balanitis (foreskin infection) in men occur. Soreness, itchiness, or white discharge can be the telltale signs and should lead to seeking medical care. If redness, swelling, pain, or fever are experienced, these can be warning signs of a dangerous bacteria infection called Fournier gangrene, a form of necrotizing fasciitis that has been reported with SGLT2 inhibitors like Farxiga. Fournier gangrene is a severe infection of the tissue of the perineum, which can involve the penis or scrotum of men and labia of women. Emergent medical treatment is needed in these circumstances.

Serious side effects of Farxiga

Hypersensitivity allergic reactions or anaphylaxis (severe allergic reaction that can be life-threatening)
Acute kidney injury or renal impairment (reduced kidney function)
Diabetic ketoacidosis (DKA)
Serious UTI
Orthostatic hypotension (drop in blood pressure upon sitting or standing up)
Fournier gangrene

Kidney injury

Early case reports indicated that SGLT2 inhibitors may be associated with acute kidney injury, a sudden decrease in kidney function. However, subsequent investigation has seemed to dispel that concern somewhat. Because Farxiga can cause one to urinate more and excessive urination can lead to dehydration, which is detrimental to kidney function, the monitoring of hydration status and kidney function is worthwhile during therapy.

Orthostatic hypotension

A drop in blood pressure precipitated by sitting up or standing up is termed orthostatic hypotension. A momentary lightheaded or dizzy feeling could occur in mild cases, but fainting could happen in more severe degrees of orthostatic hypotension. Fainting brings with it a risk for injuries such as bone fractures. The root cause for orthostatic hypotension with SGLT2 inhibitors is likely increased urination leading to a degree of dehydration. Accordingly, the prescribing healthcare provider may advise drinking plenty of fluids before starting and during therapy with Farxiga.

How long do Farxiga side effects last?

Certain Farxiga side effects may resolve with discontinuation. Urinary frequency, nausea, and constipation are examples of this category. Other Farxiga side effects, like infections and serious allergic reactions, require medical treatment to resolve. A healthcare provider or pharmacist can provide medical advice specific to your condition and symptoms.

Farxiga contraindications and warnings

Abuse and dependence

Farxiga is not habit-forming and can be stopped without fear of withdrawal syndrome.

Overdose

The maximum dose of Farxiga is 10 mg once a day. An overdose could have adverse consequences, and thus, emergency medical attention should be sought along with placing a call to the Poison Helpline at 1-800-222-1222.

Pregnancy and breastfeeding

Women in the second or third trimester of pregnancy should not take Farxiga. Women who are in the first trimester of pregnancy or who are breastfeeding should likely use an alternative medication that has more safety data from clinical trials in pregnancy and lactation. No human data is available to evaluate the effects on breast milk production or the effects on the baby.

Other Farxiga restrictions

Farxiga is not approved for children and should not be used by anyone younger than 18 years of age.

Coinciding medical conditions are another potential reason to avoid Farxiga. Renal impairment (reduced kidney function) can be one reason, specifically an estimated glomerular filtration rate of less than 45 in the setting of diabetes or less than 25 in the setting of heart failure.

Investigation into any link between Farxiga and bladder cancer is ongoing, so anyone with active bladder cancer should likely avoid the drug.

Farxiga should also not be used in the setting of:

Type 1 diabetes mellitus
Diabetic ketoacidosis (an acutely dangerous complication of diabetes)
Dialysis
Volume depletion (dehydration)
A history of hypersensitivity reaction, such as hives, to the drug or drug class

In addition, Farxiga is typically stopped in the setting of hospitalization.

Farxiga interactions

Many of Farxiga’s drug interactions are related to additive effects on kidney function or dehydration. A healthcare professional should review the patient’s full list of medications, including prescription drugs, over-the-counter agents, and supplements.

Medications that can cause kidney damage or renal function impairment, such as aminoglycoside antibiotics like gentamicin or nonsteroidal anti-inflammatory drugs like ibuprofen, are used cautiously or avoided in combination with Farxiga.
Diuretics, including furosemide, are another drug class to be wary of if used along with SGLT2 drugs, because both classes increase urine production and lead to dehydration.
Anything that causes the body to make more ketones, a process called ketosis, should also be avoided with Farxiga due to fear of DKA. Type 1 diabetes mellitus and pancreatic insulin insufficiency are classic examples of conditions that do so, but alcohol abuse is another potential risk factor. Signs of DKA include nausea, vomiting, abdominal pain, trouble breathing, and tiredness

How to avoid Farxiga side effects

Maintain adequate hydration while on Farxiga. You can ask your healthcare provider if you should drink more fluids. A low salt diet could also be problematic with Farxiga and should be discussed with your prescriber.
Avoid provided fasting or excess calorie restriction as this may increase the risk of ketoacidosis.
Before starting Farxiga, tell the prescribing healthcare professional if you have had recurrent UTIs or yeast infections, DKA, frequent alcohol use, kidney problems, or low blood pressure.
Inquire with your healthcare provider about monitoring blood sugar levels and kidney function during treatment with Farxiga. Of note, hypoglycemia (low blood sugar) is not on the list of Farxiga side effects, but it may potentiate the hypoglycemia associated with other diabetic medications, such as sulfonylureas and metformin. Potential symptoms of hypoglycemia include drowsiness, weakness, dizziness, tremor, sweating, fast heartbeat, palpitations, and anxiety.
Immediately tell the medical provider about any urinary or genital side effects or lightheadedness or dizziness.