Glimepiride

Description

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

Glimepiride appears as a white to almost white powder, exhibiting solubility in dimethyl formamide, sparing solubility in methylene chloride, and is practically insoluble in water. The structural formula is provided in the accompanying documentation.

Glimepiride tablets meet the USP drug release test 2 standards. Each tablet formulation includes the active ingredient glimepiride USP along with the following inactive ingredients: lactose monohydrate, magnesium stearate, microcrystalline cellulose, povidone, and sodium starch glycolate. Specific tablet strengths contain additional colorants: glimepiride 1 mg tablets include ferric oxide red, glimepiride 2 mg tablets contain lake blend green (comprising D&C yellow #10 aluminum lake and FD&C blue #1/brilliant blue FCF aluminum lake), and glimepiride 4 mg tablets contain lake blend blue (also comprising D&C yellow #10 aluminum lake and FD&C blue #1/brilliant blue FCF aluminum lake).

Uses and Indications

Glimepiride tablets are 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 this medication.

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 glycemic control. In patients who are at increased risk for hypoglycemia, such as the elderly or those with renal impairment, it is advised to initiate treatment with a starting dose of 1 mg and to titrate slowly to minimize the risk of adverse effects.

Contraindications

Use of this product is contraindicated in patients with a known hypersensitivity to glimepiride or any of its ingredients. Additionally, individuals with a hypersensitivity to sulfonamide derivatives should not use this product due to the potential for cross-reactivity.

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 appropriate 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 postmarketing, including severe cases such as anaphylaxis, angioedema, and Stevens-Johnson Syndrome. If a hypersensitivity reaction is suspected, glimepiride should be discontinued immediately. A thorough assessment for other potential causes of the reaction should be conducted, and alternative diabetes treatments should be initiated as necessary.

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 sulfonylureas, including glimepiride. It is essential for healthcare providers to inform patients about the risks, benefits, and available treatment alternatives.

Regarding macrovascular outcomes, it is important to note that there are no clinical studies that establish conclusive evidence of macrovascular risk reduction with glimepiride or any other anti-diabetic medication.

Healthcare professionals should remain vigilant and provide comprehensive patient education to ensure safe and effective use of glimepiride.

Side Effects

Patients may experience a range of adverse reactions while using glimepiride, which can be categorized into common and serious reactions.

Common adverse reactions include hypoglycemia, which may be severe and necessitates careful patient selection, dosing, and instructions, particularly for at-risk populations such as the elderly and those with renal impairment, as well as when used in conjunction with other anti-diabetic medications. Other common reactions reported include headache, nausea, and dizziness.

Serious adverse reactions have been documented, including hypersensitivity reactions such as anaphylaxis, angioedema, and Stevens-Johnson Syndrome. In the event of a suspected hypersensitivity reaction, glimepiride should be promptly discontinued, and alternative diabetes treatments should be considered after assessing for other potential causes. Hemolytic anemia may occur in patients with glucose 6-phosphate dehydrogenase (G6PD) deficiency, and such patients should be considered for non-sulfonylurea alternatives. Additionally, there is a potential increased risk of cardiovascular mortality associated with sulfonylureas, and patients should be informed of the risks, benefits, and available treatment alternatives. It is important to note that no clinical studies have conclusively established evidence of macrovascular risk reduction with glimepiride or any other anti-diabetic drug.

Additional adverse reactions include hypersensitivity to glimepiride or any of its ingredients, as well as hypersensitivity to sulfonamide derivatives. Severe hypoglycemia can occur, particularly in cases of glimepiride overdose, and constitutes a medical emergency requiring immediate treatment. Mild hypoglycemic episodes can typically be managed with oral glucose, while severe reactions, which may involve coma, seizure, or neurological impairment, may require glucagon or intravenous glucose. Continued observation and additional carbohydrate intake may be necessary, as hypoglycemia can recur after apparent clinical recovery.

In pediatric patients, hypoglycemic events have been documented, with blood glucose values falling below 36 mg/dL observed in 4% of those treated with glimepiride, compared to 1% in those treated with metformin. Notably, one patient in each treatment group experienced a severe hypoglycemic episode, with severity assessed by the investigator based on observed signs and symptoms.

Drug Interactions

Certain medications may influence glucose metabolism, necessitating careful dose adjustments and monitoring of blood glucose levels in patients taking glimepiride tablets.

When glimepiride is used concurrently with miconazole, there is a risk of severe hypoglycemia. Therefore, it is crucial to monitor blood glucose levels closely in such cases.

Interactions involving cytochrome P450 2C9 are significant, as both inhibitors and inducers of this enzyme can alter glimepiride plasma concentrations, potentially impacting glycemic control. Clinicians should consider these interactions when prescribing glimepiride and may need to adjust dosages accordingly.

Additionally, the coadministration of colesevelam may lead to reduced absorption of glimepiride. To mitigate this interaction, glimepiride should be administered at least 4 hours prior to colesevelam. Monitoring of blood glucose levels is advised to ensure effective glycemic control during this combination therapy.

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 tablets are not recommended for use in pediatric patients due to concerns regarding 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 pediatric patients aged 8 to 17 years, who were randomized to receive either glimepiride (n=135) or metformin (n=137). 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. Hypoglycemic events, defined as blood glucose values <36 mg/dL, were reported in 4% of pediatric patients treated with glimepiride, compared to 1% in those treated with metformin.

Geriatric Use

In clinical trials involving glimepiride, 30% of the participants (1053 out of 3491 patients) were aged 65 years and 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.

Additionally, hypoglycemia can be more challenging to recognize in geriatric patients, increasing the risk of adverse effects. Therefore, it is recommended to exercise caution when initiating therapy with glimepiride or when increasing the dosage in this population. Regular monitoring and appropriate dose adjustments may be required to ensure safety and efficacy 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.

It is important to note that poorly controlled diabetes in pregnancy is associated with significant risks to both the mother and fetus. The estimated background risk of major birth defects is 6% to 10% in women with pregestational diabetes and an HbA1c >7%, and this risk can increase to as high as 20% to 25% in women with an HbA1c >10%. The estimated background risk of miscarriage for 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.

Poorly controlled diabetes in pregnancy increases the maternal risk for diabetic ketoacidosis, preeclampsia, spontaneous abortions, preterm delivery, and delivery complications. Additionally, it raises the fetal risk for major birth defects, stillbirth, and macrosomia-related morbidity. Neonates of women with gestational diabetes who are treated with sulfonylureas during pregnancy may be at increased risk for 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.

Due to the potential for prolonged severe hypoglycemia in neonates, glimepiride tablets should be discontinued at least two weeks before the expected delivery. In animal studies, there was no increase in congenital anomalies; however, an increase in fetal deaths occurred in rats and rabbits at glimepiride doses 50 times (rats) and 0.1 times (rabbits) the maximum recommended human dose based on body surface area.

Lactation

Breastfed infants of lactating mothers using glimepiride tablets 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 infant. 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 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 tablets, similar to other sulfonylureas, can lead to severe hypoglycemia. Healthcare professionals should be vigilant in recognizing the symptoms associated with this condition.

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 benign pancreatic adenoma formation, attributed to chronic pancreatic stimulation. Notably, no adenoma formation was observed in mice at a dose of 320 ppm in complete feed, equivalent 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 evaluated for mutagenicity and 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 assessments, and the mouse micronucleus test.

Regarding fertility, glimepiride did not adversely affect male mouse fertility in animals exposed to doses up to 2,500 mg/kg body weight, which exceeds 1,500 times the maximum recommended human dose based on surface area. Additionally, no effects on fertility were observed in male and female rats administered glimepiride at doses up to 4,000 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 in the extracted data. As such, there are no additional adverse events or rare case reports to summarize.

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 healthcare providers to explain how to recognize the signs of hypoglycemia and the appropriate steps to take if they experience these symptoms.

Healthcare providers should also advise patients that hypoglycemia can impair their ability to concentrate and react, which may pose risks in situations where these abilities are critical, such as driving or operating machinery. Patients should be made aware of the importance of monitoring their blood sugar levels and recognizing when they may need to take action to prevent hypoglycemia.

Additionally, patients should be informed about the potential for hypersensitivity reactions associated with glimepiride. They should be advised to seek medical treatment immediately if they experience any signs of a hypersensitivity reaction and to discontinue the use of glimepiride if such a reaction occurs.

Storage and Handling

The product is supplied in a configuration that includes specific packaging details, which are essential for proper handling and storage. It should be stored at a temperature range of 20°-25°C (68°-77°F), in accordance with USP Controlled Room Temperature guidelines.

Healthcare professionals are advised to inspect the packaging prior to use; the product should not be utilized if the blister is torn or broken, as this may compromise the integrity of the product. Proper adherence to these storage and handling instructions is crucial to ensure the product's efficacy and safety.

Additional Clinical Information

Patients should be educated on the recognition and management of hypoglycemia, as early warning symptoms may vary or be less pronounced in individuals with autonomic neuropathy, the elderly, and those taking beta-adrenergic blocking medications or other sympatholytic agents.

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 reports of hemolytic anemia in patients receiving 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 Cardinal Health 107, LLC. It includes detailed information about indications, dosage, contraindications, warnings, and clinical pharmacology.

View full prescribing information (PDF)