Micardis Drug Interactions

MICARDIS may increase the hypotensive effect of other antihypertensive agents. Other interactions of clinical significance have not been identified.
Co-administration of telmisartan did not result in a clinically significant interaction with digoxin, warfarin, hydrochlorothiazide, glibenclamide, ibuprofen, paracetamol, simvastatin and amlodipine. For digoxin a 20% increase in median plasma digoxin trough concentration has been observed (39% in a single case), monitoring of plasma digoxin levels should be considered.
In one study the co-administration of telmisartan and ramipril led to an increase of up to 2.5 fold in the AUC_0-24 and C_max of ramipril and ramiprilat. The clinical relevance of this observation is not known.
Reversible increases in serum lithium concentrations and toxicity have been reported during concomitant administration of lithium with angiotensin converting enzyme inhibitors.
Cases have also been reported with angiotensin II receptor antagonists including MICARDIS. Therefore, serum lithium level monitoring is advisable during concomitant use.
Treatment with NSAIDs (i.e. ASA at anti-inflammatory dosage regimens, COX-2 inhibitors and non-selective NSAIDs) is associated with the potential for acute renal insufficiency in patients who are dehydrated. Compounds acting on the Renin-Angiotensin-System like telmisartan may have synergistic effects. Patients receiving NSAIDs and MICARDIS should be adequately hydrated and be monitored for renal function at the beginning of combined treatment.
A reduced effect of antihypertensive drugs like telmisartan by inhibition of vasodilating prostaglandins has been reported during combined treatment with NSAIDs.
As with other medicinal products acting on the renin-angiotensin-aldosterone system, telmisartan may provoke hyperkalaemia. The risk may increase in case of treatment combination with other medicinal products that may also provoke hyperkalaemia (salt substitutes containing potassium, potassium-sparing diuretics.
Ace inhibitors, angiotensin II receptor antagonists, non steroidal antiinflammatory medicinal products (NSAIDs, including selective, COX-2 inhibitors), heparin, immunosupressives (cyclosporin or tacrolimus), and trimethoprim).
The occurrence of hyperkalaemia depends on associated risk factors. The risk is increased in case of the above-mentioned treatment combinations. The risk is particulary high in combination with potassium sparing-diuretics, and when combined with salt subsitutes containing potassium. A combination with ACE inhibitors or NSAIDs, for example, presents as lesser risk provided that precautions for use are strictly followed.
Diuretics (thiazide or loop diuretics): Prior treatment with high dose diuretics such as furosemide (loop diuretic) and hydrochlorothiazide (thiazide diuretic) may result in volume depletion, and in a risk of hypotensin when initiating therapy with telmisartan.
Potassium sparing diuretics or potassium supplements: Angiotensin II receptor antagonists such as telmisartan, attenuate diuretic induced potassium loss. Potassium sparing diuretics e.g. spironolactone, eplerenone, triamterene, or amiloride, potassium supplements, or potassium-containing salt substitutes may lead to a significant increase in serum potassium. If concomitant use is indicated because of documented hypokalaemia, they should be used with caution and with frequent monitoring of serum potassium.
Corticosteroids (systemic route): Reduction of the antihypertensive effect.