ACE INHIBITORS, HYPERTENSIVES, MECHANISM OF ACTION, DRUGS

1. ACE INHIBITORS
Presented by
CHHAVI
M. Pharm 1st Year
Delhi Pharmaceutical Sciences & Research
University, New Delhi

2. Contents
• Introduction
• Hypertensives
• ACE Inhibitors
• Mechanism of action
• Therapeutic uses
• Adverse effects
• Contraindications & Precautions

3. Introduction
Hypertension
• Defined as either a sustained systolic blood
pressure of greater than 140 mm Hg
OR
• A sustained diastolic blood pressure of
greater than 90 mm Hg
• Hypertension results from increased
peripheral vascular smooth muscle tone,
which leads to increased arteriolar
resistance and reduced capacitance of the
venous system

4. Antihypertensives
• A class of drugs that are used to treat
hypertension
• Antihypertensive therapy seeks to
prevent the complications of high blood
pressure, such as stroke and
myocardial infarction

5. CLASSIFICATION OF
ANTIHYPERTENSIVE DRUGS
• ACE (Angiotensin Converting Enzyme)inhibitor
Captopril, Enalapril, Ramipril etc
• Angiotensin (AT1 Receptor) blocker
Losartan, Candesartan, Valsartan etc.
• Calcium channel blocker
Verapamil, Diltiazem, Nifedipine etc
• Beta Adrenergic bocker
Propanolol, Atenolol, Metoprolol
• Alpha Adrenergic blocker
Prazosin,Terazosin
• Beta & Alpha Adrenergic blocker
Labetalol, Carvedilol

6. CLASSIFICATION OF
ANTIHYPERTENSIVE DRUGS
• Diuretics
Thiazide - Hydrochlorothiazide, Chlorothiazide
High ceiling – Furosemide
Potassium sparing - Spironolactone, Amiloride
• Central Sympatholytics
Clonidine, Methyldopa.
• Vasodilators
Arteriolar - Hydralazine, Minoxidil
Arteriolar & Venous - Sodium nitroprusside
• Adrenergic neurone blocker
Reserpine, Guanethidine

7. ACE INHIBITOR
• ACE (Angiostensin converting enzyme) inhibitor is an agent which block the
angiotensin converting enzyme which ultimately inhibit the conversion of
Angiotensin - ɪɪ from Angiotensin - ɪ
Classification of ACE Inhibitor
1. Direct action but internalized metabolite to disulphide group.
Ex. captopril
2. Prodrug (Ester dicarboxylic acid)
They have the effects when they are changed to active metabolized.
Ex enalapril, benazepril
3. Soluble in water and not change in the body
Ex. lisinopril

8. MECHANISM OF ACTION
• The ACE inhibitors lower blood pressure by reducing peripheral vascular resistance.
• Block the ACE that cleaves angiotensin I to form the potent vasoconstrictor
angiotensin II.
• ACE inhibitors decrease angiotensin II and increase bradykinin levels.
• ACE inhibitors also decrease the secretion of aldosterone, resulting in decreased
sodium and water retention.

9. Drop in blood pressure
Drop in fluid volume
Angiotensinogen
Angiotensin 1
Renin release from kidney
Renin acts on Angiotensinogen to form
ACE release from lungs
ACE acts on Angiotensin 1 to form Angiotensin 2
Angiotensin 2 also acts
directly on blood vessels,
stimulating vasoconstriction
Angiotensin 2 acts on adrenal gland
to stimulate release of
Aldsosterone
RENIN
ANGIOTENSIN
SYSTEM
NaCl
H2O
Aldosterone acts on
Kidneys to stimulate
reabsorption of salt &
water
ACE Inhibitors act on
ACE to block
conversion of
Angiotensin 1 to 2

10. THERAPEUTIC USES
Used in patients with
• Cardiac failure
• Renal disease
• Systemic sclerosis
• Diabetic nephropathy
• Left ventricular hypertrophy

11. ADVERSE EFFECT
• Dry cough
• Rash
• Fever
• Hypotension (in hypovolemic states)
• Hyperkalaemia
• Fatigue
• Angioedema
• Headache
• Dizziness

12. CONTRAINDICATION &
PRECAUTION
Contraindicated in patients with
• Previous angioedema associated with
ACE inhibitor therapy
• Hypersensitivity to ACE inhibitors
Should be used with caution in patients
with
• Impaired renal function
• Hypovolemia or dehydration

13. Thank You!