Pioglitazone and glimepiride

Strong CYP2C8 inhibitors (e.g., gemfibrozil) increase pioglitazone concentrations. Limit pioglitazone dose to 15 mg daily. ( 2.3 , 7.1 ) CYP2C8 inducers (e.g., rifampin) may decrease pioglitazone concentrations. ( 7.2 ) Topiramate may decrease pioglitazone concentrations. ( 7.3 ) Certain medications may affect glucose metabolism, requiring pioglitazone and glimepiride tablet dose adjustment and close monitoring of blood glucose. ( 7.4 ) Miconazole: Severe hypoglycemia can occur when pioglitazone and glimepiride tablets and oral miconazole are used concomitantly. ( 7.5 ) CYP2C9 interactions: Inhibitors and inducers may affect glycemic control by altering glimepiride plasma concentrations.

( 7.6 ) Colesevelam: Coadministration may reduce glimepiride absorption. Pioglitazone and glimepiride tablets should be administered at least 4 hours prior to colesevelam. ( 2.4 , 7.7 )

7.1 Strong CYP2C8 Inhibitors Pioglitazone An inhibitor of CYP2C8 (e.g., gemfibrozil) significantly increases the exposure (area under the serum concentration-time curve or AUC) and half-life (t ½ ) of pioglitazone. Therefore, the maximum recommended dose of pioglitazone is 15 mg daily if used in combination with gemfibrozil or other strong CYP2C8 inhibitors.

Since the minimum dose of pioglitazone in pioglitazone and glimepiride tablets exceeds 15 mg, patients taking concomitant strong CYP2C8 inhibitors should switch to individual components of pioglitazone and glimepiride tablets, unless the prescribing health care provider determines that the benefit of pioglitazone and glimepiride tablets clearly outweighs the risk of increased pioglitazone exposure [see Dosage and Administration (2.3) and Clinical Pharmacology (12.3) ] .

7.2 CYP2C8 Inducers Pioglitazone An inducer of CYP2C8 (e.g., rifampin) may significantly decrease the exposure (AUC) of pioglitazone. Therefore, if an inducer of CYP2C8 is started or stopped during treatment with pioglitazone, changes in diabetes treatment may be needed based on clinical response without exceeding the maximum recommended daily dose of 45 mg for pioglitazone [see Clinical Pharmacology (12.3) ] .

7.3 Topiramate Pioglitazone A decrease in the exposure of pioglitazone and its active metabolites were noted with concomitant administration of pioglitazone and topiramate [see Clinical Pharmacology (12.3) ] . The clinical relevance of this decrease is unknown; however, when pioglitazone and topiramate are used concomitantly, monitor patients for adequate glycemic control.

7.4 Drugs Affecting Glucose Metabolism Glimepiride A number of medications affect glucose metabolism and may require pioglitazone and glimepiride tablet dose adjustment and particularly close monitoring for hypoglycemia or worsening glycemic control.

The following are examples of medications that may increase the glucose-lowering effect of sulfonylureas including glimepiride, a component of pioglitazone and glimepiride tablets, increasing the susceptibility to and/or intensity of hypoglycemia: oral anti-diabetic medications, pramlintide acetate, insulin, angiotensin converting enzyme (ACE) inhibitors, H2 receptor antagonists, fibrates, propoxyphene, pentoxifylline, somatostatin analogs, anabolic steroids and androgens, cyclophosphamide, phenyramidol, guanethidine, fluconazole, sulfinpyrazone, tetracyclines, clarithromycin, disopyramide, quinolones, and those drugs that are highly protein-bound, such as fluoxetine, nonsteroidal anti-inflammatory drugs, salicylates, sulfonamides, chloramphenicol, coumarins, probenecid and monoamine oxidase inhibitors. When these medications are administered to a patient receiving pioglitazone and glimepiride tablets, monitor the patient closely for hypoglycemia. When these medications are withdrawn from a patient receiving pioglitazone and glimepiride tablets, monitor the patient closely for worsening glycemic control. The following are examples of medications that may reduce the glucose-lowering effect of sulfonylureas including glimepiride, leading to worsening glycemic control: danazol, glucagon, somatropin, protease inhibitors, atypical antipsychotic medications (e.g., olanzapine and clozapine), barbiturates, diazoxide, laxatives, rifampin, thiazides and other diuretics, corticosteroids, phenothiazines, thyroid hormones, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics (e.g., epinephrine, albuterol, terbutaline), and isoniazid. When these medications are administered to a patient receiving pioglitazone and glimepiride tablets, monitor the patient closely for worsening glycemic control. When these medications are withdrawn from a patient receiving pioglitazone and glimepiride tablets, monitor the patient closely for hypoglycemia. Beta-blockers, clonidine, and reserpine may lead to either potentiation or weakening of pioglitazone and glimepiride tablets glucose-lowering effect. Both acute and chronic alcohol intake may potentiate or weaken the glucose-lowering action of pioglitazone and glimepiride tablets in an unpredictable fashion. The signs of hypoglycemia may be reduced or absent in patients taking sympatholytic drugs such as beta-blockers, clonidine, guanethidine, and reserpine.

7.5 Miconazole Glimepiride A potential interaction between oral miconazole and sulfonylureas leading to severe hypoglycemia has been reported. Whether this interaction also occurs with other dosage forms of miconazole is not known.

7.6 CYP2C9 Interactions Glimepiride There may be an interaction between glimepiride and inhibitors (e.g., fluconazole) and inducers (e.g., rifampin) of CYP2C9. Fluconazole may inhibit the metabolism of glimepiride, causing increased plasma concentrations of glimepiride which may lead to hypoglycemia. Rifampin may induce the metabolism of glimepiride, causing decreased plasma concentrations of glimepiride which may lead to worsening glycemic control.

7.7 Concomitant Administration of Colesevelam Glimepiride Colesevelam can reduce the maximum plasma concentrations and total exposure of glimepiride when the two are coadministered. However, absorption is not reduced when glimepiride is administered four hours prior to colesevelam. Therefore, pioglitazone and glimepiride tablets should be administered at least four hours prior to colesevelam [see Clinical Pharmacology (12.3) ] .

8.1 Pregnancy Risk Summary Limited data with pioglitazone and glimepiride tablets or pioglitazone in pregnant women are not sufficient to determine a drug-associated risk for major birth defects or miscarriage. There are clinical considerations related to fetal and neonatal adverse reactions and drug discontinuation if glimepiride is used during pregnancy. There are risks to the mother and fetus associated with poorly controlled diabetes in pregnancy [see Clinical Considerations ].

No adverse developmental effects were observed when pioglitazone was administered to pregnant rats and rabbits during organogenesis at exposures up to 5 and 35 times the 45 mg clinical dose, respectively, based on the body surface area. Administration of glimepiride to pregnant rats and rabbits during organogenesis induced maternal hypoglycemia and also increased fetal mortality at doses 50 (rats) and 0.1 times (rabbits) the 8 mg clinical dose, respectively, based on body surface area [see Data ] . The estimated background risk of major birth defects is 6-10% in women with pre-gestational diabetes with a HbA1c >7 and has been reported to be as high as 20-25% in women with a HbA1c >10.

The estimated background risk of miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20% respectively. Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Poorly controlled diabetes in pregnancy increases the maternal risk for diabetic ketoacidosis, pre-eclampsia, spontaneous abortions, preterm delivery, still birth and delivery complications. Poorly controlled diabetes increases the fetal risk for major birth defects, still birth, and macrosomia related morbidity.

Fetal/Neonatal Adverse Reaction Neonates of women with gestational diabetes, who are treated with sulfonylureas during pregnancy, may be at increased risk for neonatal intensive care unit admission, and may develop respiratory distress, hypoglycemia, birth injury, and be large for gestational age. Prolonged severe hypoglycemia, lasting 4-10 days, has been reported in neonates born to mothers receiving a sulfonylurea at the time of delivery and has been reported with the use of agents with a prolonged half-life. Observe newborns for symptoms of hypoglycemia and respiratory distress and manage accordingly.

Dose adjustments during pregnancy and the postpartum period Due to reports of prolonged severe hypoglycemia in neonates born to mothers receiving a…