Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated

2. ANTI-HYPERTENSIVE
DRUGS
BY:
DR. ELAF KHALID

3.  Hypertension also known as high blood pressure is a
long term medical condition in which blood pressure
in the arteries is persistently elevated.
 Hypertension is defined as a systolic pressure 140mm
Hg or more, or a diastolic of 90mm Hg or more.
INTRODUCTION
ANTI-HTN

4. Stages of HTN
ANTI-HTN
 Stages of HTN:
BP Systolic Diastolic
Normal >120 >80
Pre-hypertension 120 – 139 80-89
Stage 1 149-159 90-99
Stage 2 >160 >100

5. Types of HTN
ANTI-HTN
Types of HTN
Essential
A disorder of unknown origin
affecting blood pressure
regulating mechanism
Secondary
Secondary to known
disorder

6. Classification
ANTI-HTN
Diuretics:  Thiazides: Hydrochlorothiazide,
Chlorthalidone, Indapamide
 Loop Diuretics : Furosemide
Angiotensin-converting Enzyme
inhibitors:
Captopril, Lisinopril., Enalapril
Angiotensin (AT1 receptor) blockers Losartan, Candesartan
Direct renin inhibitor Aliskiren

7. Classification
ANTI-HTN
Calcium Channel Blockers (CCB) Verapamil, Diltiazem
ß-adrenergic blockers  Non selective: Propranolol
 Cardioselective: Metoprolol , atenolol
ß and α – adrenergic blockers Labetolol, carvedilol
α – adrenergic blockers Prazosin, terazosin, doxazosin,
Centrally acting Clonidine, methyldopa
Vasodilators  Arteriolar : Hydralazine, Minoxidil
 Arteriolar + venous: Sodium
Nitroprusside

8. Angiotensin Converting
Enzyme (ACE) Inhibitors
ANTI-HTN
Inhibit syn of
Angiotensin 2 by
inhibiting ACE
Dec in TPR &
blood volume
Fall in diastolic &
systolic BP
Captopril, Enalapril
Indications:
HTN
Heart failure
Drawbacks/ adverse effects:
I. Cough
II. Hyperkalemia

9. ANTI-HTN
Angiotensin
Receptor Blockers
(ARBs)
Angiotensin
receptor AT 1 &
AT 2 are
present on
target cells
AT receptors
when activated
causes
vasoconstriction,
aldosterone
release and salt
& water
reabsorption
ARBS act on AT
receptors and
block all the
actions mediated
by receptors and
leads to dec in
BP
Losartan, Valsartan

10. Direct renin
inhibitor
 Inhibits production of Angiotensin I & II.
 Equally effective as ACEI & ARBs.
 E.g. Aliskiren
 Adverse effects: headache & diarrhoea
ANTI-HTN

11.  Are of two types:
 Non selective: Propranolol
 Cardioselective: Metoprolol
Beta Blockers
ANTI-HTN
Dec heart rate,
contractilty,
conduction
velocity & Output
TPR inc initially
Initial phase:
Output dec, TPR
inc with little effect
on BP
Prolonged phase:
Vessels adapt to
dec CO so TPR
also dec resulting
in dec BP
Side effects:
Fatigue, lethargy (low CO)
Bradycardia
Loss of libido – impotence
broncospasm

12.  Are of two types:
 Non selective alpha blockers (Phenoxybenzamine, Phentolamine) not
used in chronic essential hypertension but used in Pheochromocytoma.
 Specific alpha-1 blockers like prazosin, terazosin and doxazosine are used
in HTN treatment
 MOA:
ANTI-HTN
Αlpha blockers
Blockade of
vasoconstritor @
receptors
Pooling of blood
in vesels leading
to dec venous
return & Cardiac
Output
Resulting
in fall of BP

13. ANTI-HTN
Alpha blockers
 Adverse effects
 Postural hypotension
 Salt and water retention
 Nasal stuffiness
 Miosis
 Failure of ejaculation in males

14.  Labetalol:
used IV for rapid BP reduction. Orally used for severe HTN.
 Carvedilol:
used as antihypertensive as well as in CHF.
ANTI-HTN
Alpha + beta
blockers

15. ANTI-HTN
Calcium Channel
Blockers
Calcium Channel Blockers
Dihydropyridines 1st generation Nefidipine
2nd generation Nicardapine
3rd generation Amlodipine
Non-Dihydropyridines Verapamil, Diltiziam
Classification:

16. ANTI-HTN
Calcium Channel
Blockers
L- type channel admits Ca
and causes depolarization
excitation- contraction
coupling
Excitation contraction
coupling causes
contraction of vascular
smooth muscles,
vasoconstriction and
elevation of BP
Blocks the L type channels
resulting in relaxation of
vascular smooth muscles
with negative chronotropic,
inotropic effect on heart
ultimately de BP
DHPS have highest smooth
muscles relaxing effect and
hence used in HTN
 MOA:
Adverse effects:
Constipation
Reflex tachycardia
hypotension

17.  Hydralazine:
 Directly acting vasodilator
 MOA:
 Uses:
 Moderate hypertension when 1st line fails
 Hypertension in Pregnancy
ANTI-HTN
Vasodilators
Causes NO
release
Relaxation of
vascular smooth
muscles
Fall in BP

18.  Sodium Nitroprusside
 Rapidly acting vasodilator (both arteriolar & venous) used in emergencies
 MOA:
 Adverse effects: Palpitation, pain abdomen, disorientation, psychosis,
weakness and lactic acidosis.
ANTI-HTN
Vasodilators
RBC convert
Nitropruside to
NO
NO causes
vasodilatation of
both arterioles &
veins
Reduing TPR & CO
and hence
resulting in dec BP

19.  Alpha-Methyl dopa:
 Alpha methyl analogue of DOPA - a prodrug
 MOA:
 Only used therapeutically now in Hypertension during pregnancy.
 Clonidine: Agonist of central alpha-2 receptor, not frequently used now
because of tolerance and withdrawal hypertension
ANTI-HTN
Centrally acting
Drugs
Converted to @
methyL noradrenaline
in brains
Acts on @-2 receptors
and inhibit adrenergic
discharge
Results in fall in BP

20.  Alpha methyl Dopa
 CCBs like Nifedipine (BUT they should be stopped before labour as they
weaken uterine contractions) –
 Cardioselective beta blockers
 Prazosin
 Clonidine
 Hydralazine
ANTI-HTN
Drugs for Hypertension
in pregnancy

21.  Hypertensive urgency : Systolic BP > 220 or diastolic BP > 120
mm Hg without overt signs of end organ damage
 Hypertensive emergencies : Systolic BP > 220 or diastolic BP >
120 mm Hg with evidence of active end organ damage.
ANTI-HTN
Drugs for Hypertensive
Emergencies

22.  Parenteral therapy:
• Sodium nitroprusside
• GTN
• Hydralazine
• Esmolol
• Phentolamine
• Labetalol :
• Furosemide
ANTI-HTN
Drugs for Hypertensive
Emergencies

23. THANKS