Contraindications of Telmisartan
Telmisartan is absolutely contraindicated in patients with known hypersensitivity to telmisartan or any component of the product, and in patients with diabetes who are taking aliskiren. 1
Absolute Contraindications
- Hypersensitivity reactions: Known hypersensitivity (e.g., anaphylaxis or angioedema) to telmisartan or any component of the product 1
- Concomitant aliskiren use in diabetic patients: Dual blockade of the renin-angiotensin system with aliskiren in diabetic patients is contraindicated due to increased risk of hyperkalemia, hypotension, and renal impairment 1
- Pregnancy: Telmisartan is contraindicated during pregnancy, particularly in the second and third trimesters, as it can cause fetal renal dysfunction, oligohydramnios, skull hypoplasia, lung hypoplasia, skeletal deformations, anuria, hypotension, renal failure, and death 1, 2
Relative Contraindications/Use with Caution
- Bilateral renal artery stenosis: Telmisartan should not be used in patients with bilateral renal artery stenosis due to risk of acute renal failure 1
- Severe hepatic impairment: As telmisartan is eliminated primarily through biliary excretion, patients with biliary obstructive disorders or hepatic insufficiency will have reduced clearance and require lower doses with careful titration 1
- Volume or salt depletion: Patients with activated renin-angiotensin system (e.g., those on high-dose diuretics) may experience symptomatic hypotension after starting telmisartan 1
- Impaired renal function: Use with caution in patients with severe congestive heart failure or renal dysfunction, as inhibiting the renin-angiotensin-aldosterone system may cause oliguria, progressive azotemia, and rarely acute renal failure 1
- Hyperkalemia risk: Use cautiously in patients with advanced renal impairment, heart failure, on renal replacement therapy, or taking potassium supplements, potassium-sparing diuretics, or potassium-containing salt substitutes 1
Special Populations
- Breastfeeding: Should be avoided during breastfeeding due to potential adverse effects on the infant 2
- Children and adolescents: Safety and efficacy not established in pediatric populations 1
- Elderly patients: No initial dosage adjustment is necessary, but close monitoring is recommended, particularly for blood pressure response 1
Drug Interactions of Concern
- ACE inhibitors: Combination with ACE inhibitors is not recommended due to increased risk of adverse effects including hyperkalemia 3, 1
- Potassium-sparing medications: Increased risk of hyperkalemia when combined with potassium-sparing diuretics, potassium supplements, or salt substitutes containing potassium 1
- NSAIDs: May reduce the antihypertensive effect of telmisartan and increase risk of renal impairment 3
Conditions Requiring Special Consideration
- Eclampsia or preeclampsia: Other agents are preferred; angiotensin receptor blockers are contraindicated 3
- Photosensitivity risk: Telmisartan may cause photosensitivity reactions, requiring sun protection measures 3
Remember that telmisartan should be discontinued immediately when pregnancy is detected to avoid serious harm to the developing fetus 3, 1.