Glimepiride

Description

Glimepiride tablets, USP are an oral sulfonylurea formulation containing the active ingredient glimepiride. The chemical structure of glimepiride is defined as 1-[[p-2-(3-ethyl-4-methyl-2-oxo-3-pyrroline-1-carboxamido) ethylphenyl]sulfonyl]-3-(trans-4-methylcyclohexyl)urea, with a molecular formula of C24H34N4O5S and a molecular weight of 490.62 g/mol.

The active ingredient appears as a white to almost white, crystalline, odorless to practically odorless powder that is practically insoluble in water. The tablets are formulated with several inactive ingredients, including lactose monohydrate, magnesium stearate, microcrystalline cellulose, povidone, sodium lauryl sulfate, and sodium starch glycolate.

Specific tablet formulations include Glimepiride 1 mg tablets, which contain Ferric Oxide Red; Glimepiride 2 mg tablets, which include FD&C Blue #2 Indigo carmine Lake and Ferric Oxide Yellow; and Glimepiride 4 mg tablets, which contain FD&C Blue #2 Indigo carmine Lake.

Uses and Indications

Glimepiride is a sulfonylurea indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus.

Limitations of use include that glimepiride is not indicated for the treatment of type 1 diabetes mellitus or diabetic ketoacidosis. There are no teratogenic or nonteratogenic effects associated with glimepiride.

Dosage and Administration

The recommended starting dose is 1 or 2 mg administered once daily. Dosing may be increased in increments of 1 or 2 mg, but such adjustments should not occur more frequently than every 1 to 2 weeks, and should be based on the patient's glycemic response. The maximum recommended dose is 8 mg once daily.

Administration should occur with breakfast or the first meal of the day to optimize efficacy. For patients at increased risk for hypoglycemia, such as the elderly or those with renal impairment, it is advised to initiate treatment with a 1 mg starting dose and to titrate slowly.

Contraindications

Use of this product is contraindicated in patients with hypersensitivity to glimepiride or any of its ingredients. Additionally, it is contraindicated in individuals with hypersensitivity to sulfonamide derivatives due to the potential for cross-reactivity and adverse reactions.

Warnings and Precautions

Patients using glimepiride should be closely monitored for several critical safety concerns.

Hypoglycemia is a significant risk associated with glimepiride, which may be severe. Healthcare professionals must ensure proper patient selection, dosing, and provide clear instructions, particularly for at-risk populations such as the elderly and those with renal impairment. Caution is also advised when glimepiride is used in conjunction with other anti-diabetic medications.

Hypersensitivity Reactions have been reported in postmarketing surveillance, including severe cases such as anaphylaxis, angioedema, and Stevens-Johnson Syndrome. If a hypersensitivity reaction is suspected, glimepiride should be discontinued immediately. The healthcare provider should assess for other potential causes of the reaction and consider alternative treatments for diabetes.

Hemolytic Anemia may occur in patients with glucose 6-phosphate dehydrogenase (G6PD) deficiency. In such cases, it is advisable to consider a non-sulfonylurea alternative to mitigate this risk.

There is a Potential Increased Risk of Cardiovascular Mortality associated with the use of sulfonylureas, including glimepiride. It is essential for healthcare providers to inform patients about the risks, benefits, and available treatment alternatives.

Lastly, while glimepiride is an effective anti-diabetic medication, there is currently no clinical evidence establishing a conclusive benefit in reducing macrovascular outcomes. Healthcare professionals should communicate this information to patients to ensure informed decision-making regarding their treatment options.

Side Effects

Common adverse reactions observed in patients include hypoglycemia, headache, nausea, and dizziness.

Serious adverse reactions may occur, with hypoglycemia being a notable concern, as it can be severe. Proper patient selection, dosing, and instructions are essential, particularly for at-risk populations such as the elderly and those with renal impairment, as well as when glimepiride is used in conjunction with other anti-diabetic medications.

Hypersensitivity reactions have been reported in postmarketing experiences, including anaphylaxis, angioedema, and Stevens-Johnson Syndrome. If a hypersensitivity reaction is suspected, glimepiride should be promptly discontinued, and alternative diabetes treatment should be initiated after assessing for other potential causes.

Hemolytic anemia may occur in patients with glucose 6-phosphate dehydrogenase (G6PD) deficiency, and a non-sulfonylurea alternative should be considered in such cases. Additionally, there is a potential increased risk of cardiovascular mortality associated with sulfonylureas, necessitating that patients are informed of the risks, benefits, and treatment alternatives. It is important to note that no clinical studies have established conclusive evidence of macrovascular risk reduction with glimepiride or any other anti-diabetic drug.

Other important considerations include hypersensitivity to glimepiride or any of its ingredients, as well as hypersensitivity to sulfonamide derivatives. Overdosage of glimepiride, similar to other sulfonylureas, can lead to severe hypoglycemia, which constitutes a medical emergency requiring immediate treatment. Mild hypoglycemic episodes can be managed with oral glucose, while severe reactions may necessitate glucagon or intravenous glucose. Continuous observation and additional carbohydrate intake may be required, as hypoglycemia can recur after apparent clinical recovery.

In pediatric patients, the profile of adverse reactions associated with glimepiride is similar to that observed in adults. Clinical trials indicated that 4% of pediatric patients treated with glimepiride experienced hypoglycemic events, with blood glucose values falling below 36 mg/dL, compared to 1% of those treated with metformin. Severe hypoglycemic episodes were reported in one patient from each treatment group, with severity assessed by the investigator based on observed signs and symptoms.

In clinical trials involving glimepiride, 30% of the 3,491 participants were over 65 years of age. While no overall differences in safety or effectiveness were noted between older and younger patients, greater sensitivity in some older individuals cannot be ruled out. Given that glimepiride is substantially excreted by the kidneys, elderly patients, who are more likely to have renal impairment, may require caution when initiating or increasing the dose of glimepiride. Furthermore, hypoglycemia may be difficult to recognize in this population.

Neonates born to women with gestational diabetes who are treated with sulfonylureas during pregnancy may face an increased risk of neonatal intensive care admission and may develop respiratory distress, hypoglycemia, birth injury, and be large for gestational age. Prolonged severe hypoglycemia lasting 4 to 10 days has been reported in neonates born to mothers receiving a sulfonylurea at the time of delivery.

Drug Interactions

Certain medications may influence glucose metabolism, necessitating careful management of glimepiride therapy.

Pharmacodynamic Interactions

• Miconazole: The concomitant use of glimepiride and oral miconazole can lead to severe hypoglycemia. Close monitoring of blood glucose levels is recommended when these agents are used together.

Pharmacokinetic Interactions

• Cytochrome P450 2C9 Inhibitors and Inducers: Agents that inhibit or induce cytochrome P450 2C9 may alter the plasma concentrations of glimepiride, potentially impacting glycemic control. It is advisable to monitor blood glucose levels closely and consider dose adjustments of glimepiride as necessary.

• Colesevelam: The coadministration of colesevelam may reduce the absorption of glimepiride. To mitigate this interaction, glimepiride should be administered at least 4 hours prior to colesevelam. Monitoring of blood glucose is recommended to ensure effective glycemic control.

Packaging & NDC

The table below lists all NDC Code configurations of Glimepiride, the U.S. brand-name prescription product. Columns show Packaging, Formulation Type, and Active Ingredient Strength.

Pediatric Use

Glimepiride is not recommended for use in pediatric patients due to its adverse effects on body weight and the risk of hypoglycemia. The pharmacokinetics of a single 1 mg dose of glimepiride was assessed in a study involving 30 patients aged 10 to 17 years with type 2 diabetes.

In a single-blind, 24-week trial, the safety and efficacy of glimepiride were evaluated in 272 patients aged 8 to 17 years, who were randomized to receive either glimepiride or metformin. Glimepiride was initiated at a dose of 1 mg, with titration to 2, 4, or 8 mg (mean final dose of 4 mg) by Week 12. Notably, hypoglycemic events, defined as blood glucose values <36 mg/dL, were reported in 4% of pediatric patients treated with glimepiride.

Geriatric Use

In clinical trials involving glimepiride, 30% of the participants (1053 out of 3491 patients) were aged 65 years or older. While no overall differences in safety or effectiveness were observed between elderly patients and their younger counterparts, it is important to note that greater sensitivity to the medication may be present in some older individuals.

Pharmacokinetic studies have shown no significant differences in the metabolism of glimepiride between patients with type 2 diabetes aged 65 years or younger (n=49) and those older than 65 years (n=42). However, glimepiride is primarily excreted by the kidneys, and elderly patients are more likely to experience renal impairment, which may necessitate careful monitoring and potential dose adjustments.

Additionally, hypoglycemia can be particularly challenging to recognize in geriatric patients, increasing the risk of adverse effects. Therefore, it is advised to exercise caution when initiating therapy with glimepiride or when increasing the dosage in this population. Regular monitoring for signs of hypoglycemia and renal function is recommended to ensure the safe use of glimepiride in elderly patients.

Pregnancy

Available data from a small number of published studies and postmarketing experience with glimepiride use in pregnancy over decades have not identified any drug-associated risks for major birth defects, miscarriage, or adverse maternal outcomes. However, sulfonylureas, including glimepiride, cross the placenta and have been associated with neonatal adverse reactions such as hypoglycemia.

Glimepiride should be discontinued at least two weeks before the expected delivery to mitigate the risk of prolonged severe hypoglycemia in neonates, which has been reported to last from 4 to 10 days in infants born to mothers receiving a sulfonylurea at the time of delivery.

Poorly controlled diabetes in pregnancy poses significant risks to both the mother and fetus. It is associated with an increased maternal risk for diabetic ketoacidosis, preeclampsia, spontaneous abortions, preterm delivery, and delivery complications. Fetal risks include major birth defects, stillbirth, and macrosomia-related morbidity. The estimated background risk of major birth defects in women with pregestational diabetes and an HbA1c >7% is 6% to 10%, escalating to as high as 20% to 25% in those with an HbA1c >10%. The background risk of miscarriage in this population remains unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.

In animal studies, glimepiride administration to pregnant rats and rabbits at doses approximately 4000 times and 60 times the maximum human dose based on body surface area did not affect embryo-fetal development. However, fetotoxicity was observed at doses 50 times and 0.1 times the maximum human dose in rats and rabbits, respectively. While there was no increase in congenital anomalies, an increase in fetal deaths was noted in these studies.

Healthcare professionals should carefully consider the risks and benefits of glimepiride use in pregnant patients and ensure optimal glycemic control to minimize potential adverse outcomes.

Lactation

Breastfed infants of lactating mothers using glimepiride should be monitored for symptoms of hypoglycemia, including jitters, cyanosis, apnea, hypothermia, excessive sleepiness, poor feeding, and seizures. It is not known whether glimepiride is excreted in human milk, and there are no data on its effects on milk production. However, glimepiride has been detected in rat milk, with significant concentrations observed during prenatal and postnatal studies in rats.

The developmental and health benefits of breastfeeding should be weighed against the mother's clinical need for glimepiride and any potential adverse effects on the breastfed child. Notably, offspring of rats exposed to high levels of glimepiride during pregnancy and lactation exhibited skeletal deformities, including shortening, thickening, and bending of the humerus, attributed to nursing from mothers exposed to the drug. Therefore, careful consideration and monitoring are advised for lactating mothers using glimepiride.

Renal Impairment

Patients with renal impairment may experience severe hypoglycemia. It is essential to ensure proper patient selection, dosing, and instructions, particularly in at-risk populations such as the elderly and those with reduced kidney function. Caution should be exercised when this medication is used in conjunction with other anti-diabetic medications to mitigate the risk of hypoglycemia. Regular monitoring of blood glucose levels is recommended to ensure patient safety and effective management.

Hepatic Impairment

Patients with hepatic impairment have not been specifically studied in relation to the use of this medication. Consequently, there are no established dosage adjustments, special monitoring requirements, or precautions outlined for individuals with compromised liver function. It is recommended that healthcare providers exercise caution when prescribing this medication to patients with hepatic impairment, given the lack of data on its safety and efficacy in this population. Regular monitoring of liver function may be prudent in these cases, although specific parameters are not defined in the available information.

Overdosage

An overdosage of glimepiride, similar to other sulfonylureas, can lead to significant hypoglycemia. Healthcare professionals should be vigilant for symptoms of hypoglycemia, which can range from mild to severe.

In cases of mild hypoglycemia, treatment can be effectively managed with the administration of oral glucose. However, severe hypoglycemic reactions are classified as medical emergencies and necessitate immediate intervention.

For patients experiencing severe hypoglycemia accompanied by coma, seizures, or neurological impairment, treatment options include the administration of glucagon or intravenous glucose. It is crucial to monitor the patient closely following initial treatment, as hypoglycemia may recur even after apparent clinical recovery. Continued observation and the provision of additional carbohydrate intake may be required to ensure the patient's safety and stability.

Nonclinical Toxicology

Studies conducted in rats at doses of up to 5000 parts per million (ppm) in complete feed, which is approximately 340 times the maximum recommended human dose based on surface area, for a duration of 30 months, demonstrated no evidence of carcinogenesis. In contrast, administration of glimepiride in mice over a 24-month period resulted in a dose-related increase in the formation of benign pancreatic adenomas, attributed to chronic stimulation of the pancreas. Notably, no adenoma formation was observed in mice at a dose of 320 ppm in complete feed, equating to 46 to 54 mg/kg body weight/day, which is at least 28 times the maximum human recommended dose of 8 mg once daily based on surface area.

Glimepiride was found to be non-mutagenic in a comprehensive array of in vitro and in vivo mutagenicity studies, including the Ames test, somatic cell mutation assays, chromosomal aberration tests, unscheduled DNA synthesis evaluations, and the mouse micronucleus test. Furthermore, glimepiride did not adversely affect male mouse fertility in animals exposed to doses of up to 2500 mg/kg body weight, which exceeds 1,500 times the maximum recommended human dose based on surface area. Similarly, no effects on fertility were observed in male and female rats administered doses of up to 4000 mg/kg body weight, approximately 4,000 times the maximum recommended human dose based on surface area.

Postmarketing Experience

No specific postmarketing experience details are available. As such, there are no additional adverse events or rare case reports to summarize at this time.

Patient Counseling

Patients should be informed about the symptoms and treatment of hypoglycemia, as well as the conditions that may predispose them to this condition. It is essential for patients to recognize signs of hypoglycemia, which can include dizziness, sweating, confusion, and palpitations, and to understand the importance of prompt treatment.

Healthcare providers should advise patients that hypoglycemia may impair their ability to concentrate and react, which can pose risks in situations requiring full attention, such as driving or operating machinery. Patients should be encouraged to take precautions in these scenarios and to monitor their blood glucose levels regularly.

Additionally, patients should be made aware that hypersensitivity reactions may occur with glimepiride. They should be instructed to seek immediate medical attention if they experience any signs of an allergic reaction, such as rash, itching, or difficulty breathing, and to discontinue the use of glimepiride if such reactions occur.

Storage and Handling

The product is supplied in well-closed containers equipped with safety closures. It should be stored at a temperature range of 20° to 25°C (68° to 77°F), in accordance with USP Controlled Room Temperature guidelines. Proper storage conditions are essential to maintain the integrity and efficacy of the product.

Additional Clinical Information

Patients should be educated on the recognition and management of hypoglycemia while being informed about the potential risks and benefits of glimepiride, as well as alternative treatment options.

Postmarketing experience has revealed reports of hypersensitivity reactions associated with glimepiride, including serious conditions such as anaphylaxis, angioedema, and Stevens-Johnson Syndrome. Additionally, there have been instances of hemolytic anemia in patients treated with glimepiride who did not have a known G6PD deficiency.

FDA Insert (PDF)

This document is the official FDA-approved prescribing information for Glimepiride as submitted by BluePoint Laboratories. It includes detailed information about indications, dosage, contraindications, warnings, and clinical pharmacology.

View full prescribing information (PDF)