What are the contraindications for telmisartan?

Telmisartan Contraindications

Telmisartan is absolutely contraindicated in patients with known hypersensitivity (including anaphylaxis or angioedema) to telmisartan or any component of the product, and must not be co-administered with aliskiren in patients with diabetes. 1

Absolute Contraindications

• Known hypersensitivity reactions including anaphylaxis or angioedema to telmisartan or any component of the formulation 1
• Co-administration with aliskiren in diabetic patients is absolutely prohibited due to increased risk of adverse effects 1

Pregnancy and Fetal Toxicity

• Pregnancy (second and third trimesters) represents a critical contraindication, as drugs acting on the renin-angiotensin system reduce fetal renal function and increase fetal and neonatal morbidity and death 1
• When pregnancy is detected, discontinue telmisartan immediately 2, 1
• Potential neonatal adverse effects include skull hypoplasia, anuria, hypotension, renal failure, and death 1
• Resulting oligohydramnios can cause fetal lung hypoplasia and skeletal deformations 1

Combination Therapy Contraindications

• Do not combine with ACE inhibitors or direct renin inhibitors, as this increases risk of hyperkalemia, hypotension, and renal dysfunction without additional benefit 2, 3, 1
• The ONTARGET trial demonstrated that combination therapy with ramipril and telmisartan resulted in more adverse events (hypotensive symptoms 4.8% vs. 1.7%, syncope 0.3% vs. 0.2%, renal dysfunction 13.5% vs. 10.2%) without increased benefit 4

High-Risk Situations Requiring Extreme Caution

Severe Bilateral Renal Artery Stenosis

• Risk of acute renal failure in patients with severe bilateral renal artery stenosis due to inhibition of the renin-angiotensin-aldosterone system 2, 3, 1
• Similar risk exists in patients whose renal function depends on renin-angiotensin-aldosterone system activity 1

Volume or Salt Depletion

• Patients on high-dose diuretics or with volume/salt depletion may experience symptomatic hypotension after initiation 1
• Correct volume depletion prior to administration or start under close medical supervision with reduced dose 1

Hepatic Impairment

• Patients with biliary obstructive disorders or hepatic insufficiency have reduced clearance since telmisartan is primarily eliminated by biliary excretion 1
• Initiate at low doses and titrate slowly in these patients 1

Common Pitfalls to Avoid

• Never restart an ACE inhibitor and telmisartan together even if the ACE inhibitor was stopped for cough—consider re-trying the ACE inhibitor alone first 1
• Monitor for hyperkalemia particularly in patients with chronic kidney disease, heart failure, those on renal replacement therapy, or taking potassium supplements, potassium-sparing diuretics, or potassium-containing salt substitutes 2, 3, 1
• Avoid in patients with history of angioedema with ARBs; if angioedema occurred with an ACE inhibitor, wait at least 6 weeks after discontinuation before starting telmisartan 2