Drug Interaction:
Patients with diuretics may occassionally experience an excessive reduction of blood pressure after initiation of therapy with amlodipine + benazepril.
Benezepril can attenuate potassium loss caused by thiazide diuretics.
Potassium sparing diuretics like spironlactone , amiloride, triamterene or potassium supplement can increase the risk of hyperkalemia.
Increase lithium levels and symptoms of litium toxicity have ben reported in patients receiving ACE inhibitors.
Benezepril has been used concomitantly with oral anticoagulants, beta -adrenergic blocking agents, calcium channel blockers, cimitedine, diuretics, digoxin, hydrazaline, and naproxyn withourt evidence of clinically important adverse interactions.
Adverse Reaction:
Edema, hamolytic anemia, angioedema, hepato-toxicity, neutropenia or agranulocytosis, pancreatitis, pemphigus, thrmbocytopenia,
dry and persistent cough, dizziness, flushing, palpitation, somnolence.
Contra-Indications:
Amlodipine Hypersensitivity,
Pregnancy.
Care to be taken in patients with sinus node disease, and in those with aortic stenosis. Benazepril Hypersensitivity
Special precautions:
Angioedema of face and extremities, lips tongue, glottis, and larynx has been reported in patients with ACE inhibitors.
Care to be taken in patients with increased angina and myocardial infarction.
Patients with congestive heart failure, with or without assoiciated renal insufficiency.
Monitor for white cell counts in patient with collagen vascular disease, especially if the disease is associated with impaired renal function.
ACE inhibitors can cause fatal and neonatal morbidity and mortality when administered to pregnant women during the second and third trimesters.
Caution to be excercised in patients with impaired renal function.
Dosages/ Overdosage Etc:
Indication-
Hypertension
Dosage-
One tablet once daily. The precsribing limit is 5mg of amlodipine and 20mg of benezepril per day. The recomended initial dose of amlodipine in elderly, small and frail patients is 2.5mg
Patient Information:
Take with or without food
Pharmacology/ Pharmacokinetics:
Pharmacology:
Amlodipine -
Amlodipine selectively inhibits calcium influx across cell membrane in cardiac and vascular smooth muscles with greater effect on vascular smooth muscle. Amlodipine is a peripheral arteriolar vasodilator.
Benazepril-
Benazepril inhibits angiotensin-converting enzyme, results in decreased plasma angiotensin II which leads to decreased vasopressor activity and decreased aldosterone secretion. The decrease in aldosterone secretion causes a small increase in serum potassium concentrations.
Combination Therapy
The combination therapy with a calcium antagonist and an ACE inhibitor provides blood pressure contro equal to that of a high dose of calcium antagonist therapy, but with with significantly fewer dosage dependent adverse experience such as vasodilatory edema.
Pharmacokinetics:
Amlodipine Benazapril
Absorption 64- 90% Approx 37% Distribution 21 L/kg 0.7L/kg Protein binding 93% 95.3% Elimination t1/2 35- 48 hrs 10- 11 hrs Tmax 6- 12 hours 0.5- 2 hours
Duration of action 24 hours 24 hours Elimination Biliary/fecal 20- 25%
Primarily renal but also biliary Renal- 70%
Interaction with Food:
Take with or without food