Untitled Quiz

Drugs Used in Hypertension

Diuretics: Reduce blood pressure by decreasing blood volume and directly affecting blood vessels.
- Thiazide Diuretics: Inhibit sodium and chloride transport in the Distal Convoluted Tubules.
  - Examples: Hydrochlorothiazide, Chlorthalidone, and Metolazone
  - Uses: Hypertension and heart failure.
  - Side Effects: Hypokalemic metabolic acidosis.
- Loop Diuretics: Inhibit sodium, potassium, and chloride transport in the thick ascending loop of Henle.
  - Examples: Furosemide, Torsemide, and Ethacrynic Acid.
  - Uses: Heart failure and pulmonary edema
  - Particularly effective in edematous states and fluid overload.
  - Side Effects:
    - Ototoxicity (hearing loss)
    - Hypokalemia (low potassium)
    - Dehydration
    - Allergy to Sulfa
    - Nephritis (kidney inflammation)
    - Gout (arthritis)
Sympathoplegics: Interfere with the sympathetic nervous system's control of cardiovascular function.
- By reducing: venous tone, heart rate, contractile force of the heart, cardiac output and total peripheral resistance.
- Uses: Hypertension, Pre-eclampsia.
- Examples: Clonidine, Alpha-1 blockers, and Beta Blocks.
Sympathoplegics
Centrally Acting Alpha 2 Agonists: Stimulates alpha-2 receptors in the central nervous system to reduce sympathetic outflow.
- Clonidine: Reduces heart rate and relaxes blood vessels.
  - Side Effects: Rebound hypertension and dry mouth.
  - Taper before discontinuing to avoid rebound hypertension.
- Methyldopa: Used for maintenance treatment of hypertension in pregnancy.
  - Side Effects: Hemolytic anemia.
Adrenergic Blockers: Block receptors for the hormones epinephrine (adrenaline) and norepinephrine (noradrenaline) to reduce their effects.
- Alpha Adrenergic Blockers: Block alpha-1 receptors, primarily located in the blood vessels and smooth muscle.
  - Examples: Prazosin, Doxazosin, Terazosin, Tamsulosin, Silodosin, Alfuzosin.
  - Uses: Benign Prostatic Hyperplasia (enlarged prostate gland).
  - Side Effects: First dose syncope (fainting) and orthostatic hypertension (low blood pressure upon standing).
  - Tamsulosin: Most selective for prostatic smooth muscle.
- Beta Adrenergic Blockers: Block beta receptors, located on the heart and other tissues.
  - Examples: Metoprolol, Propanolol, Atenolol, Nebivolol, Esmolol, Carvedilol.
  - Uses: Hypertension, Migraine, Glaucoma.
  - Side Effects: Heart Failure, erectile dysfunction
  - Must not be given in acute heart failure
  - Can be used in chronic heart failure.

Vasodilators

Medications that open/dilate blood vessels.
- Effects: Relaxes muscles in the walls of arteries and veins, preventing them from tightening and narrowing.
- Result: Blood flows more easily and the heart doesn't have to pump as hard, reducing blood pressure.

Vasodilators

Oral Vasodilators
- Hydralazine:
  - Uses: Preeclampsia, Hypertension.
  - Side Effects: Severe psychiatric depression, suicidal ideation.
- Minoxidil:
  - Uses: Alopecia (hair loss), Hypertension.
  - Side Effects: Hirsutism (excessive hair growth), Angina, Drug-induced lupus.
  - Stimulates hair follicles.

Vasodilators

Parenteral Vasodilators
- Nitroprusside:
  - MOA: Relaxes venous and arteriolar smooth muscle by increasing nitric oxide (NO) → ↑ cGMP → smooth muscle relaxation.
  - Uses: Hypertensive emergency, Acute heart failure.
  - Side Effects: Cyanide toxicity, hypotension, headache.
  - Most effective vasodilator.
- Fenoldopam:
  - MOA: Arteriolar vasodilation of afferent (incoming) and efferent (outgoing) arterioles. Increases renal blood flow.
  - Uses: Hypertensive emergency.
  - Side Effects: Hypotension, Hypokalemia.

Calcium Channel Blockers

Medications that lower blood pressure and treat symptoms such as chest pain and irregular heartbeat.
Block the L-type calcium channels in the body.
Stops calcium from entering the cells of the heart and the arteries.
Calcium causes the heart and arteries to squeeze more strongly.
By blocking calcium, CCBs allow blood vessels to relax and open.
Types of Calcium Channel Blockers:
- Non-dihydropyridine CCB:
  - Verapamil, Diltiazem.
- Dihydropyridine CCB:
  - Amlodipine, Nicardipine.
Common Side Effects: Constipation, Pretibial Edema.

Calcium Channel Blockers

Non-Dihydropyridine CCB
- Verapamil:
  - MOA: Cardiac > Vascular
  - More cardioselective CCB
  - Preferred CCB for arrhythmia
  - Uses: Supraventricular tachycardia (SVT)
  - Side Effects: Gingival hyperplasia (Verapamil) (gum overgrowth).

Calcium Channel Blockers

Dihydropyridine CCB
- Amlodipine, Nifedipine, Felodipine, Nicardipine.
- MOA: Vascular > Cardiac
- Common Uses: Hypertension-related chest pain (Angina)
- Side Effects: Edema, Flushing, Dizziness