Dapagliflozin and metformin

You should not use this medicine if you are allergic to dapagliflozin (Farxiga) or metformin (Glucophage, Actoplus Met, Avandamet, Fortamet, Glucovance, Janumet, Jentadueto, Kazano, Kombiglyze, Metaglip, PrandiMet, Riomet), or if you have:

• moderate to severe kidney disease (or if you are on dialysis); or

• metabolic acidosis or diabetic ketoacidosis (call your doctor for treatment).

If you need to have any type of x-ray or CT scan using a dye that is injected into your veins, you will need to temporarily stop taking dapagliflozin and metformin.

Some people taking metformin develop a serious condition called lactic acidosis. This may be more likely if you have liver or kidney disease, congestive heart failure, surgery, a heart attack or stroke, a severe infection, if you are 65 or older, if you are dehydrated, or if you drink a lot of alcohol. Talk with your doctor about your risk.

To make sure dapagliflozin and metformin is safe for you, tell your doctor if you have ever had:

• liver or kidney disease;

• low blood pressure;

• a bladder infection or urination problems;

• bladder cancer;

• heart problems;

• problems with your pancreas, including surgery; or

• if you are on a low salt diet.

It is not known whether dapagliflozin and metformin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether dapagliflozin and metformin passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.

Dapagliflozin and metformin is not approved for use by anyone younger than 18 years old.

Dapagliflozin and metformin combination is used to treat a type of diabetes mellitus called type 2 diabetes. It is used together with a proper diet and exercise to help control blood sugar levels.

Dapagliflozin works in the kidney to prevent absorption of glucose (blood sugar). This helps lower the blood sugar level. Metformin reduces the absorption of sugar from the stomach, reduces the release of stored sugar from the liver, and helps your body use sugar better. It does not help patients who have insulin-dependent or type 1 diabetes. Type 1 diabetic patients must use insulin injections.

dapagliflozin and metformin is available only with your doctor's prescription.

(dap a gli FLOE zin & met FOR min)

The manufacturer recommends to avoid metformin since hepatic disease is considered a risk factor for the development of lactic acidosis during metformin therapy. However, continued use of metformin in diabetics with hepatic dysfunction, including cirrhosis, has been used successfully and may be associated with a survival benefit in carefully selected patients; use cautiously in patients at risk for lactic acidosis (eg, renal impairment, alcohol use) (Brackett 2010; Zhang 2014). No dosage adjustment is necessary for dapagliflozin in patients with mild to severe hepatic impairment according to the manufacturer's labeling for dapagliflozin.

Alcohol (Ethyl): May enhance the adverse/toxic effect of MetFORMIN. Specifically, alcohol may potentiate the risk of lactic acidosis Avoid combination

Alpha-Lipoic Acid: May enhance the hypoglycemic effect of Antidiabetic Agents. Monitor therapy

Androgens: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Exceptions: Danazol. Monitor therapy

BuPROPion: May increase the serum concentration of OCT2 Substrates. Monitor therapy

Carbonic Anhydrase Inhibitors: May enhance the adverse/toxic effect of MetFORMIN. Specifically, the risk of developing lactic acidosis may be increased. Exceptions: Brinzolamide; Dorzolamide. Monitor therapy

Cephalexin: May increase the serum concentration of MetFORMIN. Monitor therapy

Cimetidine: May increase the serum concentration of MetFORMIN. Management: Consider alternatives to cimetidine in patients receiving metformin due to a potential for increased metformin concentrations and toxicity (including lactic acidosis). Consider therapy modification

Dalfampridine: MetFORMIN may increase the serum concentration of Dalfampridine. Dalfampridine may increase the serum concentration of MetFORMIN. Monitor therapy

Dofetilide: MetFORMIN may increase the serum concentration of Dofetilide. Monitor therapy

Dolutegravir: May increase the serum concentration of MetFORMIN. Management: Limit the daily metformin dose to 1,000 mg when used together with dolutegravir. Metformin dose adjustments may also be needed upon discontinuation of dolutegravir. Monitor patient response to metformin closely. Consider therapy modification

Glycopyrrolate (Systemic): May increase the serum concentration of MetFORMIN. Monitor therapy

Guanethidine: May enhance the hypoglycemic effect of Antidiabetic Agents. Monitor therapy

Hyperglycemia-Associated Agents: May diminish the therapeutic effect of Antidiabetic Agents. Monitor therapy

Hypoglycemia-Associated Agents: Antidiabetic Agents may enhance the hypoglycemic effect of Hypoglycemia-Associated Agents. Monitor therapy

Insulin: SGLT2 Inhibitors may enhance the hypoglycemic effect of Insulin. Management: Consider a decrease in insulin dose when initiating therapy with a sodium-glucose cotransporter 2 inhibitor and monitor patients for hypoglycemia. Consider therapy modification

Iodinated Contrast Agents: May enhance the adverse/toxic effect of MetFORMIN. Renal dysfunction that may be caused by iodinated contrast agents may lead to metformin-associated lactic acidosis. Management: Management advice varies. Refer to the full drug interaction monograph content for details. Exceptions: Diatrizoate Meglumine; Ethiodized Oil. Consider therapy modification

Isavuconazonium Sulfate: May increase the serum concentration of MetFORMIN. Monitor therapy

LamoTRIgine: May increase the serum concentration of MetFORMIN. Management: The lamotrigine Canadian product monograph states that coadministration of these drugs is not recommended. Monitor therapy

MAO Inhibitors: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Ombitasvir, Paritaprevir, and Ritonavir: May enhance the adverse/toxic effect of MetFORMIN. Specifically, the risk for lactic acidosis may be increased. Monitor therapy

Ombitasvir, Paritaprevir, Ritonavir, and Dasabuvir: May enhance the adverse/toxic effect of MetFORMIN. Specifically, the risk for lactic acidosis may be increased. Monitor therapy

Ondansetron: May increase the serum concentration of MetFORMIN. Monitor therapy

Patiromer: May decrease the serum concentration of MetFORMIN. Management: Administer metformin at least 3 hours before or 3 hours after patiromer. Consider therapy modification

Pegvisomant: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Prothionamide: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Quinolone Antibiotics: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Quinolone Antibiotics may diminish the therapeutic effect of Blood Glucose Lowering Agents. Specifically, if an agent is being used to treat diabetes, loss of blood sugar control may occur with quinolone use. Monitor therapy

Ranolazine: May increase the serum concentration of MetFORMIN. Management: Limit the metformin dose to a maximum of 1700 mg/day when used together with ranolazine 1000 mg twice daily. Consider therapy modification

Salicylates: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Selective Serotonin Reuptake Inhibitors: May enhance the hypoglycemic effect of Blood Glucose Lowering Agents. Monitor therapy

Sulfonylureas: SGLT2 Inhibitors may enhance the hypoglycemic effect of Sulfonylureas. Management: Consider a decrease in sulfonylurea dose when initiating therapy with a sodium-glucose cotransporter 2 inhibitor and monitor patients for hypoglycemia. Consider therapy modification

Thiazide and Thiazide-Like Diuretics: May diminish the therapeutic effect of Antidiabetic Agents. Monitor therapy

Topiramate: May enhance the adverse/toxic effect of MetFORMIN. Monitor therapy

Trimethoprim: May increase the serum concentration of MetFORMIN. Monitor therapy

Trospium: MetFORMIN may decrease the serum concentration of Trospium. Monitor therapy

Vandetanib: May increase the serum concentration of MetFORMIN. Monitor therapy

Verapamil: May diminish the therapeutic effect of MetFORMIN. Monitor therapy

Concerns related to adverse effects:

• Bone fractures: Increased incidence of bone fractures may occur in patients with renal impairment.

• Genital mycotic infections: Dapagliflozin may increase the risk of genital mycotic infections (eg, vulvovaginal mycotic infection, vulvovaginal candidiasis, vulvovaginitis, candida balanitis, balanoposthitis). Patients with a history of these infections or uncircumcised males are at greater risk.

• Hypersensitivity reactions: Patients may experience hypersensitivity reactions (eg, angioedema, urticaria), with some being severe, due to dapagliflozin. Discontinue if hypersensitivity occurs and treat as appropriate.

• Hypotension: May cause symptomatic hypotension due to intravascular volume depletion especially in patients with renal impairment (eGFR <60 mL/minute/1.73 m2), elderly, patients on other antihypertensives (eg, diuretics, ACE inhibitors, or angiotensin receptor blockers [ARBs]), or those with low systolic blood pressure. Assess volume status prior to initiation in patients at risk of hypotension and correct if depleted; monitor for signs and symptoms of hypotension after initiation.

• Ketoacidosis: Cases of ketoacidosis, a serious and life-threatening condition resulting in urgent hospitalization, have been reported in patients with type 1 and type 2 diabetes mellitus receiving sodium-glucose cotransporter 2 (SGLT2) inhibitors; in some cases, patients have presented with normal or only modestly elevated blood glucose (<250 mg/dL) (Bobart 2016; FDA 2015; Handelsman 2016). Before initiating treatment, consider risk factors that may predispose to ketoacidosis (eg, pancreatic insulin deficiency, dose decreases or discontinuation of insulin, caloric restriction, alcohol abuse, extensive exercise, myocardial infarction, stroke, severe infection, surgery, any other extreme stress event) (Handelsman 2016). The American Association of Clinical Endocrinologists and American College of Endocrinology recommend considering withholding of SGLT2 inhibitors for at least 24 hours prior to events that may precipitate diabetic ketoacidosis (Handelsman 2016), while others have suggested withholding for 3 to 5 days (Bobart 2016). Patients presenting with nausea/vomiting, abdominal pain, generalized malaise, and/or shortness of breath should be assessed immediately for ketoacidosis; if indicated, consider interruption or discontinuation of therapy.

• Lactic acidosis: [US Boxed Warning]: Postmarketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. The onset is often subtle, accompanied by nonspecific symptoms (eg, malaise, myalgias, respiratory distress, somnolence, abdominal pain); elevated blood lactate levels (>5 mmol/L); anion gap acidosis (without evidence of ketonuria or ketonemia); increased lactate:pyruvate ratio; metformin plasma levels generally >5 mcg/mL. Risk factors for lactic acidosis include patients with renal impairment, concomitant use of certain drugs (eg, carbonic anhydrase inhibitors such as topiramate), ≥65 years, having a radiologic study with contrast, surgery and other procedures, hypoxic states (eg, acute heart failure), excessive alcohol intake, and hepatic impairment. Discontinue immediately if lactic acidosis is suspected; prompt hemodialysis is recommended. Lactic acidosis should be suspected in any patient with diabetes receiving metformin with evidence of acidosis but without evidence of ketoacidosis. Discontinue metformin in patients with conditions associated with dehydration, sepsis, or hypoxemia. The risk of accumulation and lactic acidosis increases with the degree of impairment of renal function.

• Lipid abnormality: Dapagliflozin may increase LDL-cholesterol (C); monitor and treat as needed.

• Renal effects: Acute kidney injury has been reported with dapagliflozin. Prior to initiation, consider risk factors for acute kidney injury (eg, hypovolemia, chronic renal insufficiency, heart failure, use of concomitant medications [eg, diuretics, ACE inhibitors, angiotensin receptor blockers, or NSAIDs]). Temporarily discontinue use with reduced oral intake or fluid losses; discontinue use if acute kidney injury occurs. Additional abnormalities in renal function (decreased eGFR, increased serum creatinine) and adverse effects related to renal function may occur. Assess renal function prior to initiation and periodically during treatment.

• Urinary tract infection: Serious urinary infections, including urosepsis and pyelonephritis requiring hospitalization, have been reported; treatment with SGLT2 inhibitors, including dapagliflozin, increases the risk for urinary tract infections (UTI); monitor for signs and symptoms of UTI and treat as needed.

• Vitamin B12 concentrations: Long-term metformin use is associated with vitamin B12 deficiency; monitor vitamin B12 serum concentrations periodically with long-term therapy. Monitoring of B12 serum concentrations should be considered in all patients receiving metformin and in particular those with peripheral neuropathy or anemia (ADA 2017c).

Disease-related concerns:

• Bladder cancer: Newly diagnosed bladder cancer occurred more frequently in dapagliflozin patients; causal relationship could not be established. Do not use in patients with active bladder cancer; weigh the benefits of glycemic control versus the unknown risks for cancer recurrence in patients with a history of bladder cancer.

• Heart failure: Use with caution in patients with congestive heart failure requiring pharmacologic management, particularly in patients with unstable acute heart failure; risk of lactic acidosis may be increased secondary to hypoperfusion. In a scientific statement from the American Heart Association, metformin has been determined to be an agent that may exacerbate underlying myocardial dysfunction (magnitude: major) (AHA [Page 2016]).

• Hepatic impairment: Use with caution in patients with impaired liver function due to potential for lactic acidosis.

• Renal impairment: Metformin is substantially excreted by the kidney; assess renal function prior to initiation of therapy and periodically thereafter using estimated glomerular filtration rate (eGFR); the risk of metformin accumulation and lactic acidosis increase with degree of renal impairment. Use of combination product is contraindicated in patients with moderate to severe renal impairment (eGFR <60 mL/minute/1.73 m2). Use of concomitant medications that may affect renal function (ie, affect tubular secretion) may also affect metformin disposition. Metformin should be withheld in patients with dehydration and/or prerenal azotemia.

• Stress-related states: It may be necessary to discontinue metformin and administer insulin if the patient is exposed to stress (fever, trauma, infection, surgery).

Concurrent drug therapy issues:

• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Special populations:

• Elderly: Use with caution; risk of metformin-associated lactic acidosis increases with age.

Other warnings/precautions:

• Appropriate use: Not for use in patients with diabetic ketoacidosis (DKA) or patients with type 1 diabetes mellitus (insulin-dependent, IDDM).

• Ethanol use: Instruct patients to avoid excessive acute or chronic ethanol use; ethanol may potentiate metformin's effect on lactate metabolism.

• Iodinated contrast: Temporarily discontinue metformin at the time of or before iodinated contrast imaging procedures in patients with a history of hepatic disease, alcoholism, or heart failure; or in patients who will receive intra-arterial iodinated contrast. Reevaluate eGFR 48 hours after imaging procedure; restart if renal function is stable. Alternatively, the American College of Radiology (ACR) guidelines recommend that metformin may be used prior to or following administration of iodinated contrast media in patients with no evidence of acute kidney injury (AKI) and with an eGFR ≥30 mL/minute/1.73 m2; ACR guidelines recommend temporary discontinuation of metformin in patients with known AKI or severe chronic kidney disease ([stage IV or V [ie, eGFR <30 mL/minute/1.73 m2]) or who are undergoing arterial catheter studies (ACR 2015).

• Patient education: Diabetes self-management education (DSME) is essential to maximize the effectiveness of therapy.

• Surgical procedures: Metformin should be withheld 24 hours before surgery (all other oral hypoglycemic agents should be withheld the morning of surgery or procedure) (ADA 2017d). Resume only after normal oral intake resumed and normal renal function is verified.

Not recommended in patients with hepatic impairment.

Contraindicated

This drug should not be used during the second and third trimesters of pregnancy. AU TGA pregnancy category: D US FDA pregnancy category: C

In animal studies, dapagliflozin exposure during periods of animal development corresponding to the late second and third trimesters of human development, showed increased kidney weights and renal pelvic and tubular dilation. There are no adequate and well-controlled studies of this drug or its individual components in pregnant women. AU TGA pregnancy category D: Drugs which have caused, are suspected to have caused or may be expected to cause, an increased incidence of human fetal malformations or irreversible damage. These drugs may also have adverse pharmacological effects. Accompanying texts should be consulted for further details. US FDA pregnancy category D: There is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

In rat studies, direct and indirect exposure to dapagliflozin during late pregnancy and weaning having been associated with an increased incidence and/or severity of renal pelvic and tubular dilations. These periods of exposure coincide with a critical window of renal maturation in rats. Additionally, this drug is associated with weight loss. There are no studies in lactating animals using the combined components of this drug nor are there reports in human lactation.

AU: Contraindicated during lactation US, UK: Use is not recommended and a decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother. Excreted into human milk: Unknown (dapagliflozin); Yes, in small amounts (metformin) Excreted into animal milk: Yes (dapagliflozin); Yes (metformin) A risk to the newborns/infants cannot be excluded.