Related Experiment Video
Updated: Aug 15, 2026

Getting to Compliance in Forced Exercise in Rodents: A Critical Standard to Evaluate Exercise Impact in Aging-related Disorders and Disease
Published on: August 22, 2014
Ephedrine plus caffeine causes age-dependent cardiovascular responses in Fischer 344 rats
Reuben Howden1, Paul R Hanlon, John G Petranka
1Laboratory of Respiratory Biology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
Abstract:
Human consumption of ephedrine and caffeine in dietary supplements has been associated with a number of adverse effects including changes in the ECG, myocardial infarction, hyperthermia, and, in rare instances, death. The purpose of this study was to investigate the potential mechanisms associated with the cardiotoxicity of combined ephedrine and caffeine ingestion. Seven- and fourteen-week-old Fischer 344 rats treated with ephedrine in combination with caffeine exhibited increases in heart rate (HR), temperature, and corrected QT interval. Of the 14-wk-old rats treated with 25 mg/kg ephedrine plus 30 mg/kg caffeine, 57% died within 3-5 h of treatment, whereas none of the similarly treated 7-wk-old rats nor any of the rats treated with vehicle died. One hour after treatment with this dose of ephedrine plus caffeine, 14-wk-old rats exhibited a larger increase in HR (as % increase over baseline) than 7-wk-old rats. Furthermore, the 14-wk-old rats that died had a higher HR and temperature than the 14-wk-old rats that lived. Histopathological studies suggested interstitial hemorrhage and myofiber necrosis in the 14-wk-old rats treated with the highest concentration of ephedrine and caffeine. This study showed enhanced susceptibility to ephedrine plus caffeine in 14-wk-old rats compared with 7-wk-old rats. The greater mortality in the 14-wk-old rats was associated with increases in body temperature, HR, and myocardial necrosis.
More Related Videos
08:33Experimental Protocol for Examining Behavioral Response Profiles in Larval Fish: Application to the Neuro-stimulant Caffeine
Published on: July 24, 2018
07:49A Pacing-Controlled Procedure for the Assessment of Heart Rate-Dependent Diastolic Functions in Murine Heart Failure Models
Published on: July 21, 2023
Related Concept Videos
Adrenergic Agonists: Mixed-Action Agents
Ephedrine and pseudoephedrine lack a catecholamine group, making them less susceptible to degradation by metabolic enzymes. They have increased oral bioavailability and lipophilicity, resulting in a longer duration of action. Their response is reduced by...
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
Drug Dosing: Geriatric Patients
Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Absorption
Pharmacokinetics in Geriatric Patients: Effect of Age on Drug Distribution
Pharmacodynamics in Geriatric Patients: Effects of Age