Lecture Notes: Anti-Hypertensives

Overview

• Anti-Hypertensives: Medications to lower blood pressure.
• Blood Circulation: Heart pumps oxygenated blood through arteries; returns via veins.
• Cardiac Output: Affect blood pressure; calculated by cardiac output × total peripheral resistance (TPR).

Blood Pressure Basics

• Mean Arterial Pressure: Calculated as cardiac output × TPR.
• Systolic Pressure: Pressure when the heart pumps blood out.
• Diastolic Pressure: Pressure when heart fills with blood.
• Normal BP: 120/80 mm Hg.
• Hypertension: High blood pressure; serious if untreated.

Anti-Hypertensive Medications

Grouped by Alphabet: A, B, C, D, E

A: ACE Inhibitors, Angiotensin Receptor Blockers, Alpha 1 Receptor Blockers

ACE Inhibitors

• Mechanism: Inhibit angiotensin converting enzyme; reduce Angiotensin 2.
• Examples: Captopril (ends in "pril").
• Side Effects: Dry cough, rash, nausea, vomiting, diarrhea, angioedema, headache.
• Contraindications: Pregnancy, asthma, chronic cough, kidney disease.

Angiotensin Receptor Blockers (ARBs)

• Mechanism: Block Angiotensin 2 binding to receptors.
• Examples: Losartan (ends in "sartan").
• Side Effects: Headache, nausea, dizziness, back pain.
• Contraindications: Pregnancy, renal stenosis.

Alpha 1 Receptor Blockers

• Mechanism: Inhibit noradrenaline/adrenaline on vessels; decrease blood pressure.
• Effects: Reduce cholesterol, treat high BP and cholesterol.
• Side Effects: Hypotension.

B: Beta Blockers

• Mechanism: Block beta receptors; reduce sympathetic activity.
• Focus: Heart (selective) or periphery (non-selective).
• Examples: Metoprolol (ends in "ol").
• Side Effects: Bradycardia, fatigue, hypotension, decreased libido, bronchoconstriction.
• Contraindications: Obstructive lung disease, peripheral vascular disease.

C: Calcium Channel Blockers

• Mechanism: Block T-type and L-type calcium channels.
• Examples: Verapamil, Nifedipine ("dine" ending).
• Effects: Decrease heart rate, cardiac output, smooth muscle contraction.
• Side Effects: Flushing, headache, dizziness, palpitations.
• Contraindications: Heart failure, hypotension, ventricular tachycardia.

D: Diuretics

• Mechanism: Induce diuresis in kidneys; decrease fluid, BP.
• Types:
  • Loop Diuretics
  • Thiazide Diuretics
  • Potassium-Sparing Diuretics
• Side Effects: Electrolyte imbalances, metabolic alkalosis, pancreatitis.
• Contraindications: Specific to type of diuretic.

E: Endothelin Receptor Antagonists

• Mechanism: Relax blood vessels; decrease BP.
• Side Effects: Headache, edema, nasal congestion, nausea.

Conclusion

• Summarized anti-hypertensive medications by categories A to E.
• Key Takeaways:
  • Understand mechanisms and side effects.
  • Consider contraindications for effective treatment.