ACE Inhibitors

Submitted by Thiruvelan on Thu, 06/24/2010
Hypertension Medicine ACE Inhibitors

Angiotensin is a natural chemical in the body causes the arteries to become narrow. Angiotensin-converting enzyme (ACE) forms the angiotensin. ACE inhibitors limit the ACE activity, thus lessen angiotensin formation, which lowers blood pressure.

ACE inhibitor medications

Mechanism of Action - These drugs inhibits angiotensin- converting enzyme. Increased formation of bradykinin and vasodilator prostaglandins. Decreased secretion of aldosterone help sodium excretion.

Commonly prescribed ACE inhibitors on the market, include:

  1. Benazepril hydrochloride (brand name: Lotensin)
  2. Captopril (brand name: Capoten)
  3. Enalapril maleate (brand name: Vasotec)
  4. Fosinopril sodium (brand name: Monopril)
  5. Lisinopril (brand name: Prinivel & Zestril)
  6. Moexipril (brand name: Univasc)
  7. Perindopril (brand name: Aceon)
  8. Quinapril hydrochloride (brand name: Accupril)
  9. Ramipril (brand name: Altace)
  10. Trandolapril (brand name: Mavik)
  11. Imidapril hydrochloride (brand name: Tanatril)

Advantages of ACE inhibitor – It improves glucose tolerance and insulin resistance. It possess protecting against renal glomerular especially in diabetes mellitus. Do not adversely affect quality of life.

ACE (Angiotensin converting enzyme) inhibitors are the drugs of choice for patients with heart failure, chronic kidney failure, or heart attack (myocardial infarction that weakens the heart muscle).

As per new recommendation by the British Hypertension Society; ACE inhibitors are the first-line drug for patients who are younger than 55.

The ACE inhibitor is recommended for people with diabetes who have increased protein levels in the urine (proteinuria), heart failure, or a prior heart attack. An ACE inhibitor may be the first drug choice for a person with kidney disease.

For whom ACE inhibitor medication is suitable?

An ACE inhibitor may be suitable for the heart failure treatment with preserved left ventricular function (diastolic dysfunction) and systolic heart failure. Diastolic dysfunction is characterized by normal heart contraction, but the left ventricle is not relaxing properly, so less blood enters the heart. Systolic dysfunction is characterized by heart muscle not contracting with enough force, thus less amount of oxygen-rich blood pumped throughout the body.

When to take ACE inhibitor?

It should usually take on an empty stomach, preferably one hour before meals.

Why are ACE inhibitors contraindicate for people with renal artery stenosis?

ACE inhibitors for people with renal artery stenosis will cause hypoperfusion of the kidneys that will lead to renal failure.

Why ACE inhibitors cause an excessive cough in some?

ACE inhibitors may associate with a dry, persistent cough in 5 to 35% of patients. The mechanism of a cough is likely multifactorial; it prevents the breakdown of bradykinin and substance P, resulting in its accumulation in the respiratory tract.

Why ACE inhibitors cause hyperkalemia?

Inhibition of ACE will reduce the concentration of angiotensin II. It reduces the secretion of aldosterone and secretion of potassium, thus leading to hyperkalemia.

How do ACE inhibitors help reduce proteinuria?

Lungs secrete angiotensin converting enzyme (ACE) in response to hypotension (low BP) or hypovolemia (low blood volume). This enzyme converts angiotensin into more powerful vasoconstrictor angiotensin II, which help increase blood pressure.

Angiotensin II may also directly contribute to accelerating renal damage by sustaining cell growth, inflammation, and fibrosis. ACE inhibitors that inhibit the activity of the renin-angiotensin-aldosterone system (RAAS) are renoprotective and may slow or even halt the proteinuria or progression of chronic nephropathies.

Hypertension and diabetes exert harmful effects on the kidney via angiotensin II and overusing the kidneys to get rid of waste, both of which are lessened by ACE inhibitors.

Why is ACE inhibitor contraindicate for bilateral renal stenosis?

Renal artery stenosis is an arterial narrowing that carries blood to one or both of the kidneys. Your body is sensing this low blood supply to the kidneys and mistakenly interpret it as having low blood pressure. It signals the release of kidney hormones to increase blood pressure.

ACE inhibitor triggers drop in the intraglomerular and filtration pressures. ACE inhibitors do not directly reduce the renal blood flow but drop the glomerular perfusion pressure hence leads to acute renal function deterioration.

Who should avoid ACE inhibitor?

Avoid ACE inhibitor, if you are pregnant (this medicine has risk in late pregnancy), kidney or liver problems, diabetes, heart problems, and taking diuretics.

What are the side effects of ACE inhibitors?

Skin rash (6%), loss of taste, chronic dry hacking cough (in about 10 - 30%, it is the most common and distressing symptom), tiredness, headache, nausea, vomiting, sleeping problems, dizziness, fast heartbeat, reduced sexual function, liver damage, chest pain, and rarely kidney damage.

Women who plan to get pregnant and on ACE inhibitors for hypertension treatment should change the class of drugs. ACE inhibitor has been shown to be dangerous to both mother and baby during pregnancy. It might cause low blood pressure, kidney failure, high potassium level and even death of the newborn.

Frequently, the ACE inhibitor has an association with a dry cough and rarely with angioedema (0.2% life threatening); if you are one, then can you choose ARBs instead.

What are the warning signs of ACE inhibitor?

Consult a doctor immediately if you are having chest pain, breathing or swallowing problems, swelling of the face, eyes, lips, tongue, or legs.