Linagliptin Pharos (Linagliptin)

Linagliptin acts on the dipeptidyl peptidase‑4 pathway to manage hyperglycaemia in type 2 diabetes.

• Type 2 diabetes mellitus (monotherapy): improves blood glucose levels when used alone with diet and exercise.
• Type 2 diabetes mellitus (combination therapy): enhances glycaemic control when added to metformin, sulfonylureas or insulin.
• Patients with renal impairment: can be used without dose adjustment, providing an option for those with reduced kidney function.

• Linagliptin selectively inhibits the enzyme dipeptidyl peptidase‑4 (DPP‑4), preventing the breakdown of the incretin hormones GLP‑1 and GIP. Elevated incretin levels increase glucose‑dependent insulin secretion from pancreatic β‑cells and suppress glucagon release from α‑cells, resulting in reduced hepatic glucose production and lower post‑prandial blood glucose concentrations.

Linagliptin may be associated with a range of adverse reactions, which are categorised by frequency and severity.

Common Side Effects

• Nasopharyngitis: mild inflammation of the nose and throat.
• Headache: transient head pain of mild to moderate intensity.
• Upper respiratory tract infection: symptoms such as cough and congestion.
• Dizziness: occasional sensation of light‑headedness.

Serious or Rare Side Effects

• Pancreatitis: severe abdominal pain with elevated enzymes requiring immediate medical attention.
• Severe hypersensitivity reactions: including rash, angioedema or anaphylaxis.
• Bullous pemphigoid: rare skin disorder characterised by blistering lesions.
• Hepatic injury: marked elevation of liver enzymes or jaundice.

Before initiating Linagliptin, clinicians should consider several precautionary measures to ensure safe use.

• Renal impairment: monitor kidney function, although dose adjustment is not required.
• Hepatic impairment: use with caution in patients with moderate to severe liver disease.
• Cardiovascular disease: assess risk, as hypoglycaemia may be more problematic when combined with insulin.
• Pregnancy and lactation: avoid unless the potential benefit outweighs the risk; discuss with a healthcare professional.
• Concomitant insulin or sulfonylureas: monitor for signs of hypoglycaemia and adjust therapy as needed.
• Store below 25°C: keep in the original packaging, protect from moisture and light.

Linagliptin can interact with other medicines, and interactions are classified by their clinical significance.

Major Interactions (Avoid)

• Insulin or sulfonylureas: increased risk of hypoglycaemia; dose adjustment may be required.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin): may raise linagliptin plasma levels.
• Strong P‑glycoprotein inhibitors (e.g., itraconazole): can increase exposure and risk of adverse effects.

Moderate Interactions (Monitor Closely)

• Rifampin: induces metabolism and may reduce linagliptin efficacy.
• Thiazide diuretics: may blunt glucose‑lowering effect.
• ACE inhibitors or ARBs: monitor blood pressure and renal function when combined.
• NSAIDs: may affect renal function, requiring periodic assessment.