Related Experiment Video

Updated: Aug 29, 2025

Microfluidics in Assessing Platelet Function
06:47

Microfluidics in Assessing Platelet Function

Published on: November 8, 2024

1.0K

Comparative antiplatelet effects of chlorthalidone and hydrochlorothiazide

Khalid Bashir1, Tammy Burns2, Samuel J Pirruccello3

  • 1Creighton University School of Medicine, Omaha, Nebraska, USA.

Journal of Clinical Hypertension (Greenwich, Conn.)
|September 6, 2022
PubMed

Insights

Chlorthalidone and hydrochlorothiazide do not exhibit antiplatelet effects in healthy volunteers. Aspirin demonstrated significant antiplatelet activity, suggesting other mechanisms may explain the cardiovascular benefits of these hypertension medications.

Area of Science:

  • Cardiovascular Pharmacology
  • Thrombosis Research
  • Clinical Trial Design

Background:

  • Chlorthalidone (CTD) and hydrochlorothiazide (HCTZ) are diuretics used for hypertension management.
  • CTD may offer superior cardiovascular event reduction compared to HCTZ.
  • A potential mechanism for CTD's benefit could involve antiplatelet effects.

Purpose of the Study:

  • To investigate and compare the antiplatelet effects of CTD, HCTZ, and aspirin (ASA) in healthy volunteers.
  • To determine if CTD or HCTZ influence platelet activation and aggregation.

Main Methods:

  • Prospective, double-blind, randomized, three-way crossover study.
  • Evaluation of platelet activation and aggregation using five standard platelet agonists.
  • Comparison of pre- and post-treatment effects in 34 healthy volunteers.

Main Results:

  • Aspirin (ASA) showed statistically significant antiplatelet effects.
  • Neither Chlorthalidone (CTD) nor Hydrochlorothiazide (HCTZ) demonstrated significant antiplatelet effects.
  • Hypokalemia incidence was 0% for ASA, 30% for CTD, and 18% for HCTZ.

Conclusions:

  • The cardiovascular benefits of CTD and HCTZ in hypertensive patients are unlikely due to antiplatelet mechanisms.
  • Hypokalemia was more frequent with CTD in this study than reported in a major hypertension outcome trial.
  • Further research is needed to clarify the clinical relevance of observed hypokalemia rates.

Keywords:
antihypertensive therapyclinical pharmacologyhypertension-generalpharmacologic (drug) therapypotassium/hypertension

More Related Videos

Ferric Chloride-induced Murine Thrombosis Models10:37

Ferric Chloride-induced Murine Thrombosis Models

Published on: September 5, 2016

21.9K
Perturbing Endothelial Biomechanics via Connexin 43 Structural Disruption09:20

Perturbing Endothelial Biomechanics via Connexin 43 Structural Disruption

Published on: October 4, 2019

5.6K

Related Concept Videos

Antihypertensive Drugs: Thiazide-Class Diuretics01:15

Antihypertensive Drugs: Thiazide-Class Diuretics

Thiazide diuretics are sulfonamide derivatives featuring a benzothiadiazine ring system in their molecular structure. Based on this structure, thiazide diuretics can be categorized into two groups: thiazide-type and thiazide-like diuretics. Thiazide-type diuretics, including hydrochlorothiazide and chlorothiazide, consist of a benzothiadiazine backbone with an attached sulfonamide group. Thiazide-like diuretics, such as chlorthalidone and indapamide, lack the thiazide ring but demonstrate...
825
Antiplatelet Drugs: Prostaglandin Synthesis, P2Y12 and Glycoprotein IIb/IIIa Inhibitors01:20

Antiplatelet Drugs: Prostaglandin Synthesis, P2Y12 and Glycoprotein IIb/IIIa Inhibitors

Antiplatelet drugs emerge as frontline defenders against the insidious threat of thromboembolic diseases, where abnormal clots obstruct vital blood vessels. These drugs stand as bulwarks, inhibiting platelet aggregation and clot formation, thereby mitigating the risk of life-threatening conditions like myocardial infarction, coronary artery disease, and thrombotic strokes.
Prostaglandin synthesis inhibitors, exemplified by the widely known aspirin, wield their power by irreversibly acetylating...
618
Antihypertensive Drugs: Angiotensin II Receptor Blockers01:30

Antihypertensive Drugs: Angiotensin II Receptor Blockers

In the renin-angiotensin-aldosterone system, a hormone called angiotensin II plays a crucial role. It binds to the AT1 receptors in vascular smooth muscles coupled with Gq proteins. The activation of these receptors activates an enzyme called phospholipase C, which releases two molecules: inositol trisphosphate and diacylglycerol. These molecules cause a chain reaction that leads to the phosphorylation of myosin light chains and promotes interaction between actin and myosin, leading to smooth...
889
Antihypertensive Drugs: Direct Renin Inhibitors01:25

Antihypertensive Drugs: Direct Renin Inhibitors

The renin-angiotensin-aldosterone system (RAAS) is an intricate physiological pathway involving numerous enzymes and hormones, including renin, angiotensin-converting enzyme (ACE), angiotensin I and II, and aldosterone. Imbalances within this system increase the production of angiotensin II and aldosterone. Increased angiotensin II levels promote vasoconstriction and blood pressure elevation. Concurrently, higher aldosterone levels stimulate sodium and water reabsorption in the kidneys,...
799
Antihypertensive Drugs: Potassium-Sparing Diuretics01:28

Antihypertensive Drugs: Potassium-Sparing Diuretics

Liddle syndrome is a genetically inherited form of hypertension characterized by the overactivity of epithelial sodium channels in the nephron, the functional unit of the kidney. This heightened activity leads to increased sodium reabsorption and excessive excretion of potassium. To counteract this, potassium-sparing diuretics such as amiloride are used. They function by blocking these sodium channels, thereby reducing the influx of sodium into the epithelial cells and minimizing the loss of...
713
Antihypertensive Drugs: Action of Diuretics01:16

Antihypertensive Drugs: Action of Diuretics

Diuretics are antihypertensive drugs used to treat hypertension resulting from sodium and water retention. Sodium, vital for fluid balance and nerve or muscle function, is regulated by the kidneys through millions of nephrons. Blood enters nephrons via afferent arterioles, which branch into capillaries called glomeruli. These filter blood plasma, allowing water and solutes, like sodium ions, to pass through capillary walls into Bowman's capsule. The filtrate then flows through various...
846