Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Drug toxicity: Drug–Drug Interaction

Drug toxicity: Drug–Drug Interaction

Drug–drug interactions can precipitate toxicity through multiple mechanisms. Absorption interactions alter how drugs enter the body, exemplified when ranitidine increases the absorption of basic drugs, while cholestyramine decreases the levels of propranolol. Protein binding interactions occur when drugs share the same binding sites on plasma proteins. Drugs like aspirin and warfarin, when bound in excess, can lead to increased free drug concentrations, enhancing the potential for...

Pharmacokinetics: Drug–Drug Interactions

Pharmacokinetics: Drug–Drug Interactions

Drug interactions occur when the pharmacological effect of one drug is altered by another substance, either enhancing or diminishing its activity. The drug whose activity is altered is known as the object drug, and the substance causing the alteration is called the agent drug or the precipitant. The net effects of these interactions are mostly undesirable, leading to decreased effectiveness or increased adverse effects. In rare cases, interactions can be beneficial, such as the enhanced...

Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants

Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants

Oral anticoagulants are vital tools in preventing and treating blood clotting disorders. This diverse class of medications can be categorized as vitamin K antagonists, exemplified by warfarin, and direct thrombin inhibitors (DTIs), such as dabigatran, as well as factor Xa inhibitors, including rivaroxaban.
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...

Factors Affecting Renal Clearance: Drug Distribution and Drug Interactions

Factors Affecting Renal Clearance: Drug Distribution and Drug Interactions

Renal clearance plays a pivotal role in drug elimination from the body and can be influenced by drug distribution and interactions. Understanding these factors is crucial in pharmacology as they impact the effectiveness and duration of drug therapy.
One important factor is the relationship between renal clearance and the apparent volume of distribution. Renal clearance tends to be inversely proportional to the apparent volume of distribution. Drugs with an extensive distribution volume or those...

Antihypertensive Drugs: Potassium-Sparing Diuretics

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...

Renal Failure: Dose Adjustments

Renal Failure: Dose Adjustments

In patients with renal impairment, drugs undergo significant changes in their pharmacokinetics, which require dosage adjustments to ensure safe and effective therapy.
Reduced renal clearance and elimination rate are common outcomes of renal impairment. These alterations lead to a prolonged elimination half-life and an altered apparent volume of distribution for drugs. As a result, dosage adjustments are typically necessary to maintain optimal drug levels in the body.
However, dosage adjustments...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

A mixed-methods study exploring free nicotine replacement therapy as a strategy to promote tobacco treatment equity at Cancer Center Cessation Initiative sites.

Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer·2025

Same author

ATR-FTIR and multivariate analysis for differential diagnosis of dengue and leptospirosis: a feasibility study.

Scientific reports·2025

Same author

Wisconsin Young Adults' Attitudes, Beliefs, Motivations, and Behaviors Surrounding E-Cigarette Use and Cessation.

WMJ : official publication of the State Medical Society of Wisconsin·2025

Same author

Wisconsin Adolescents' Attitudes, Beliefs, Motivations, and Behaviors Surrounding E-Cigarette Use and Cessation.

WMJ : official publication of the State Medical Society of Wisconsin·2025

Same author

Bleeding Definitions in Pediatric Extracorporeal Membrane Oxygenation (ECMO) Studies: A Systematic Review and Meta-Analysis.

ASAIO journal (American Society for Artificial Internal Organs : 1992)·2025

Same author

Validation of the Malta Gait Scale: A Time-Efficient Tool for Poststroke Assessment.

Stroke research and treatment·2025

Search research articles

Related Experiment Video

Updated: Jun 27, 2026

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation

Published on: February 28, 2012

Probable interaction between warfarin and torsemide.

Jennifer Bird¹, Carlos Carmona

¹College of Pharmacy, University of Oklahoma Health Sciences Center, Oklahoma City, OK Clinical Pharmacy Specialist, Oklahoma City Veterans Affairs Medical Center, Oklahoma City, OK 73104, USA. jennifer.bird@va.gov

The Annals of Pharmacotherapy

|November 20, 2008

Summary

Torsemide may increase warfarin's anticoagulant effect by interfering with its metabolism and protein binding. This potential drug interaction necessitates awareness among healthcare providers to ensure patient safety.

Related Experiment Videos

Last Updated: Jun 27, 2026

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation

Published on: February 28, 2012

Area of Science:

Pharmacology
Clinical Medicine
Drug Metabolism

Background:

Warfarin is a widely used anticoagulant medication.
Torsemide is a loop diuretic often prescribed for conditions like congestive heart failure.
Effective anticoagulation management requires careful monitoring of drug interactions.

Observation:

A patient on a stable warfarin regimen experienced a significant increase in International Normalized Ratio (INR) after initiating torsemide.
The patient's warfarin dosage required reduction to maintain therapeutic anticoagulation.
Clinical factors such as fluid status and levothyroxine dosage were ruled out as causes for the INR change.

Findings:

Torsemide likely potentiated warfarin's anticoagulant effect through two proposed mechanisms: competition for CYP2C9 metabolism and protein-binding displacement.
Competition for CYP2C9 may decrease warfarin clearance, leading to higher drug concentrations.
Protein-binding displacement can transiently increase the free fraction of warfarin, enhancing its anticoagulant activity.

Implications:

This case suggests a potential drug interaction between torsemide and warfarin, which has not been previously reported.
Healthcare providers should be vigilant for this interaction, especially in patients receiving both medications.
Further research is warranted to confirm the interaction and elucidate its precise mechanisms.