Brands, Medical Use, Clinical Data
Drug Category
- Antihypertensive Agents
- Angiotensin-converting Enzyme Inhibitors
Dosage Forms
Brands / Synonyms
Acovil; Altace; Carasel; Cardace; Delix; Hytren; Lostapres; Pramace; Quark; Ramace; Ramipril [Usan:Ban:Inn]; Ramiprilum [Latin]; Triatec; Tritace; Unipril; Vesdil
Indications
For diuretics and digitalis in congestive heart failure as adjunctive therapy and for use in prophylaxis in post MI.
Pharmacology
Ramipril is an angiotensin-converting enzyme (ACE) inhibitor similar to benazepril, fosinopril, and quinapril. An inactive prodrug, ramipril is converted to ramiprilat in the liver and is used to treat hypertension and heart failure, to reduce proteinuria and renal disease in patients with nephropathies, and to prevent stroke, myocardial infarction, and cardiac death in high-risk patients.
Mechanism of Action
Ramiprilat, the active metabolite, competes with angiotensin I for binding at the angiotensin-converting enzyme, blocking the conversion of angiotensin I to angiotensin II. As angiotensin II is a vasoconstrictor and a negative-feedback mediator for renin activity, lower concentrations result in a decrease in blood pressure and an increase in plasma renin. Ramiprilat may also act on kininase II, an enzyme identical to ACE that degrades the vasodilator bradykinin.
Absorption
The extent of absorption is at least 50-60% and is not significantly influenced by the presence of food in the GI tract, although the rate of absorption is reduced.
Toxicity
The most likely clinical manifestations would be symptoms attributable to hypotension. LD50 = 10933 mg/kg (orally in mice).
Biotrnasformation / Drug Metabolism
Hepatic
Contraindications
ALTACE is contraindicated in patients who are hypersensitive to this product or any other angiotensin converting
enzyme inhibitor (e.g., a patient who has experienced angioedema during therapy with any other ACE inhibitor.
Drug Interactions
With nonsteroidal anti-inflammatory agents: Rarely, concomitant treatment with ACE
inhibitors and nonsteroidal anti-inflammatory agents have been associated with worsening of renal failure and an
increase in serum potassium.
With Diuretics: Patients on diuretics, especially those in whom diuretic therapy was recently
instituted, may occasionally experience an excessive reduction of blood pressure after initiation of therapy with
ramipril. The possibility of hypotensive effects with ramipril can be minimized by either discontinuing the diuretic
or increasing the salt intake prior to initiation of treatment with ramipril. If this is not possible, the starting
dose should be reduced.
With Potassium Supplements and Potassium-sparing Diuretics: Ramipril can attenuate potassium loss
caused by thiazide diuretics. Potassium-sparing diuretics (spironolactone, amiloride, triamterene, and others) or
potassium supplements can increase the risk of hyperkalemia. Therefore, if concomitant use of such agents is
indicated, they should be given with caution, and the patient's serum potassium should be monitored frequently.
With Lithium: Increased serum lithium levels and symptoms of lithium toxicity have been reported in
patients receiving ACE inhibitors during therapy with lithium. These drugs should be coadministered with caution, and
frequent monitoring of serum lithium levels is recommended. If a diuretic is also used, the risk of lithium toxicity
may be increased.
Other: Neither ramipril nor its metabolites have been found to interact with food, digoxin, antacid,
furosemide, cimetidine, indomethacin, and simvastatin. The combination of ramipril and propranolol showed no adverse
effects on dynamic parameters (blood pressure and heart rate). The co-administration of ramipril and warfarin did not
adversely affect the anticoagulant effects of the latter drug. Additionally, co-administration of ramipril with
phenprocoumon did not affect minimum phenprocoumon levels or interfere with the subjects' state of
anti-coagulation.
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