What are the key characteristics of Tradjenta (linagliptin), including brand and generic name, dosage forms, pharmacologic category, FDA-approved indications, dosage and frequency, mechanism of action, contraindications, adverse effects, drug interactions, and patient counseling points?

Tradjenta (Linagliptin): Key Characteristics and Clinical Information

Tradjenta (linagliptin) is a DPP-4 inhibitor that requires no dose adjustment in renal impairment, is administered as a 5 mg once-daily oral tablet, and is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. 1

A. Brand and Generic Name

• Brand name: Tradjenta (also marketed as Trajenta, Trazenta, or Trayenta in different countries)
• Generic name: Linagliptin 1, 2

B. Dosage Forms

• 5 mg light red, round, biconvex, bevel-edged, film-coated tablets with "D5" debossed on one side and the Boehringer Ingelheim symbol on the other side 1

C. Pharmacologic Category

• Dipeptidyl peptidase-4 (DPP-4) inhibitor 1, 3
• Oral antihyperglycemic agent

D. FDA-Approved Indications

• Indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus 1

Limitations of Use:

• Not recommended for patients with type 1 diabetes mellitus
• Has not been studied in patients with a history of pancreatitis 1

E. Dosage and Frequency

• 5 mg taken orally once daily, with or without food 1
• No dose adjustment required for renal impairment, hepatic impairment, elderly, or obesity 4, 1

F. Mechanism of Action

• Linagliptin is a selective inhibitor of dipeptidyl peptidase-4 (DPP-4), an enzyme that rapidly degrades incretin hormones (GLP-1 and GIP) 5
• By inhibiting DPP-4, linagliptin increases endogenous levels of GLP-1 and GIP 3
• These incretin hormones enhance insulin secretion and inhibit glucagon secretion in a glucose-dependent manner 3, 6
• This results in improved glycemic control with HbA1c reductions of approximately 0.4-0.9% 4, 2

G. Contraindications

• Hypersensitivity to linagliptin or any excipients in Tradjenta 1
• Reactions such as anaphylaxis, angioedema, exfoliative skin conditions, urticaria, or bronchial hyperreactivity have been reported 1

H. Adverse Effects

• Most common adverse reaction (≥5% incidence and more often than placebo): nasopharyngitis 1
• Other reported adverse effects include:
  • Pancreatitis (including fatal cases) 1, 3
  • Hypoglycemia (primarily when used with insulin or sulfonylureas) 1
  • Hypersensitivity reactions 1
  • Severe and disabling arthralgia 1
  • Bullous pemphigoid 1
  • Postmarketing reports of joint pain 4

I. Drug Interactions

• Strong P-glycoprotein/CYP3A4 inducers (e.g., rifampin): May reduce efficacy of linagliptin; use of alternative treatments is strongly recommended 1, 7
• Insulin secretagogues (e.g., sulfonylureas): Increased risk of hypoglycemia; consider lower doses of the insulin secretagogue 1
• Insulin: Increased risk of hypoglycemia, particularly in patients with severe renal impairment 1
• Antimicrobials (especially fluoroquinolones and sulfamethoxazole-trimethoprim): May increase effective dose of sulfonylureas when used concomitantly with linagliptin, potentially precipitating hypoglycemia 3

J. Patient Counseling Points

• Take 5 mg once daily, with or without food 1
• Report symptoms of pancreatitis (severe abdominal pain that may radiate to the back, with or without vomiting) 1
• Be aware of increased hypoglycemia risk when used with insulin or sulfonylureas 1
• Report any signs of hypersensitivity reactions (rash, skin flaking, hives, swelling of face or throat, difficulty breathing) 1
• Report development of severe joint pain 1
• Report development of blisters or erosions (signs of bullous pemphigoid) 1
• No dose adjustment needed for kidney problems, unlike most other diabetes medications 3, 4
• Monitor for signs of heart failure (shortness of breath, rapid weight gain, swelling) 1
• Linagliptin is not a substitute for insulin in insulin-dependent patients 1
• Continue diet and exercise as part of diabetes management 1

Linagliptin's unique advantage is its primarily non-renal elimination route, making it the only DPP-4 inhibitor that requires no dose adjustment in patients with any degree of renal impairment 3, 4, 8.