The presentation contains a brief description on the antihypertensive drugs

1. ANTIHYPERTENSIVE
DRUGS
PRESENTED BY:
NIRMALYA DEY (18601916079)
NEHA ROY (18601916080)
B.PHARM. 3RD YEAR, 6TH SEM (SEC-B)
GURU NANAK INSTITUTE OF PHARMACEUTICAL SCIENCE
AND TECHNOLOGY.

2. CONTENT:
➢ INTRODUCTION
➢ DRUG CLASSIFICATION
➢ ANGIOTENSIN CONVERTING ENZYME INHIBITORS (ACEIs)
➢ ANGIOTENSIN RECEPTOR BLOCKERS (ARBs)
➢ CALCIUM CHANNEL BLOCKERS (CCBs)
➢ DIURETICS
➢ SYMPATHOLYTICS
➢ GANGLIONIC BLOCKERS
➢ ADRENERGIC NEURONAL BLOCKERS
➢ VASODILATORS
➢ ANTIHYPERTENSIVES DURING PREGNANCY
➢ CONCLUSION
➢ REFERENCES

3. INTRODUCTION
 As per WHO (1999), hypertension may be defined as either a sustained
systolic blood pressure (SBP) of >140mmHg, or a sustained diastolic blood
pressure (DBP) of >90mmHg.
 An agent that reduces high BP, is called an ANTIHYPERTENSIVE.
Causes:
➢ Increase in total cholesterol level
➢ Increase in Total Peripheral Resistance (TPR)
➢ Increase in Cardiac output (CO)
➢ Increase in blood volume

4. DRUG CLASSIFICATION
 1) ACE Inhibitors: Captopril, Enalapril, Lisinopril, Perindopril.
 2) Angiotensin Receptor Blockers: Losartan, Candesartan, Irbesartan.
 3) Calcium Channel Blockers: Nifedipine, Amlodipine, Verapamil, Diltiazem.
 4) Diuretics:
 a) Thiazide diuretics – Hydrochlorthiazide, Chlorthalidone.
 b) High-ceiling/Loop diuretics – Furosemide, Torsemide.
 c) K+ sparing diuretics – Spironolactone, Eplerenone.
 5) Sympatholytics:

5. (contd…) DRUG CLASSIFICATON
 a) Beta Adrenergic blockers: Atenolol, Propranolol, Esmolol, Metoprolol.
 b) Selective Alpha-1 Adrenergic blockers: Prazosin, Terazosin.
 c) Alpha + Beta Adrenergic blockers: Labetalol, Carvediol
 d) Centrally-acting sympatholytics: Clonidine, Methyl-D-dopa.
 6) Ganglionic blockers: Pentolinium, Trimethaphan, Clonidium.
 7) Adrenergic neuronal blockers: Reserpine, Guanethidine.
 8)Vasodilators:
 a) Arteriolar – Diazoxide, Minoxidil.
 b) Arteriolar + Venodilator – Sodium-nitroprusside.

6. ACE INHIBITORS (ACEIs)

7. (contd…) ACE INHIBITORS
 Mechanism of Action:
 - Inhibit generation of AT-2
 - Inhibit degradation of Bradykinin, which is a potent vasodilator
 - Dilate both arteries and veins
 - Blood flow to vital organs increases
 - Decrease aldosterone production indirectly
 Pharmacokinetics: Well absorbed orally; poorly cross BBB; metabolized in liver; excreted
through urine.
 Duration of action of Captopril – 8-12 hrs.
 ADRs: Cough, Teratogenic, Skin rashes, Loss of taste sensation, Hyperkalemia.
 Uses: Hypertension, CHF, MI, Diabetic nephropathy.

8. ANGIOTENSIN RECEPTOR BLOCKERS
 Mechanism of Action: Competitively inhibit binding of AT-2 to AT-1 receptors.
• ADRs and Uses are almost similar to that of the ACEIs, except that, ARBs do
not increase bradykinin levels and so, the ACEI related cough isn’t
encountered. Angioedema and taste disturbance is also rare.

9. DIURETICS
 Mechanism of Action:
 Inhibit Na+ - Cl- symport in early DCT → Promote Na+ and water retention →
Decrease Na+ conc. in vascular smooth muscles → Decrease in plasma volume
and peripheral resistance → Decrease in BP
 ADRs: Hypokalemia, Hypercalcemia, Hyperglycemia, etc.
 Uses: Hypertension, Renal dysfunction, nephrogenic diabetes insipidus.

10. GANGLIONIC BLOCKERS
 Mechanism of Action:
 Act on, and block sympathetic ganglia → interrupt adrenergic control of
arterioles → Vasodilation → Decrease BP
 ADRs: Hypotension, Neuromuscular blockade, Dry mouth, Constipation.
 Uses: Hypertension, Peripheral vascular diseases.

11. ADRENERGIC NEURONAL BLOCKERS
 Mechanism of Action: They act by blocking adrenergic receptors in target
organs, or by inhibiting the synthesis, storage, or release of endogenous
catecholamines (mainly Norepinephrine), and cause decrease in CO and
vascular resistance.
 ADRs: Mild postural hypotension
 Uses: Hypertension, Anti-psychotic, Anti-emetic

12. VASODILATORS
 Minoxidil: Opens K+ channel → Hyperpolarization of vascular smooth muscles
→ Vasodilation → Decreases BP
 Diazoxide: Activates Ca+ channel in the arteriolar smooth muscle → Direct
smooth muscle relaxation → Decreases BP
 ADRs: Chest pain, Heart palpitations (fluttering or pounding heartbeat),
Dizziness, Headache, etc.
 Uses: Hypertension, Angina, Heart failure.

13. ANTIHYPERTENSIVES IN PREGNANCY
 Drugs to be avoided:
 Diuretics – Risk of placental wastage, still birth.
 ACEIs – Risk of foetal damage, growth retardation.
 Beta-blockers – Neonatal bradycardia, hypoglycaemia.
 Safe drugs: Hydralazine, Alpha-methyldopa, CCBs, Prazosin, Clonidine,
Cardioselective beta-blockers.

14. CONCLUSION
 Choice of drugs for any patient should be individualized. Patients undergoing
antihypertensive medications in diabetes, or during pregnancy are at higher
risk of clinical cardiovascular events and benefit more from antihypertensive
therapy, compared to the non-diabetic/ non-pregnant patients. It is thus,
important for the clinicians to monitor these patients so that, they can be
conscientiously treated.

15. REFERENCES
➢ Essentials of Medical Pharmacology by K.D. Tripathi (8th edition): Ch- 41,
Antihypertensive Drugs; Pg. 604-620 & Ch- 36, Drugs affecting Renin-
Angiotensin System; Pg. 524-539.
➢ Medicinal Chemistry by D. Sriram & P. Yogeeswari (2nd edition): Ch- 16,
Antihypertensive Agents; Pg. 328-347.

16.  THANK YOU!