Related Experiment Video
Updated: Jul 26, 2026

Disrupting Reconsolidation of Fear Memory in Humans by a Noradrenergic β-Blocker
Published on: December 18, 2014
Inhibition of (-)-propranolol hydrochloride by its enantiomer in white mice--a placebo-controlled randomized study
R M Kuzeff1, R P Mecheva, M N Topashka-Ancheva
1Graduate School of Integrative Medicine, Swinburne University of Technology, Melbourne, Australia. kuzeffm@ausdoctors.org
Background:
A previous pilot study was performed to see if toxicity of (S)-(-)-propranolol hydrochloride may be inhibited by a potentized preparation of its enantiomer. The present study is based on the hypothesis that the toxic effects of an optical isomer, may be counteracted or reversed by the administration of a potentized preparation of one of its stereoisomers, and in particular the enantiomer.
Methods:
508 ICR conventional mice were used. 254 mice were administered (R)-(+)-propranolol HCl homeopathic potency prior to and during the experiment, and the other 254 were administered indistinguishable placebo. On the day of the experiment mice were anesthetized with intraperitoneal Rometar. Once sedated the mice were administered the LD50 dose of (-)-propranolol HCl intraperitoneally.
Results:
The end point for statistical analysis was the difference in survival between the placebo and treatment mice. The odds ratio for survival of treatment mice relative to placebo mice was 1.52. The hypothesis of equal survival proportions gave a chi-square of 5.0429 (1 degree of freedom), which has a p-value of 0.0247. The analysis was then adjusted for mouse weight and intraperitoneal (-)-propranolol dosage using a logistic regression (LR) model. The LR treatment odds ratio was 1.51 and the LR treatment chi-square was 4.8112 (1 degree of freedom), which has a p-value of 0.0283. Consequently, we reject the null hypothesis of no treatment effect on survival. Eleven percent more treatment mice survived than placebo mice.
Conclusion:
We conclude that the toxicity of intraperitoneal (-)-propranolol HCl, may be counteracted by administration of a potency of its enantiomer, in ICR conventional mice which have survived preceding intraperitoneal Rometar injection, and pre-dosing with (+)-propranolol HCl homeopathic potency.
Insights
This study investigated if (R)-(+)-propranolol HCl homeopathic potency could reduce the toxicity of (-)-propranolol HCl. Results showed a significant increase in survival rates for mice treated with the homeopathic preparation, suggesting a protective effect.
Area of Science:
- Pharmacology
- Toxicology
- Homeopathy
Background:
- Previous pilot studies suggested that homeopathic preparations of enantiomers might inhibit drug toxicity.
- This study tested the hypothesis that stereoisomers can counteract toxic effects of optical isomers.
Purpose of the Study:
- To determine if (R)-(+)-propranolol hydrochloride homeopathic potency can counteract the toxicity of (-)-propranolol hydrochloride.
- To evaluate the effect of enantiomer administration on survival rates following toxic drug exposure.
Main Methods:
- 508 ICR mice were divided into two groups: one received (R)-(+)-propranolol HCl homeopathic potency, the other received placebo.
- Mice were anesthetized and administered the LD50 dose of (-)-propranolol HCl intraperitoneally.
- Survival rates were statistically analyzed and adjusted for mouse weight and dosage using logistic regression.
Main Results:
- Mice pre-treated with (R)-(+)-propranolol HCl homeopathic potency showed a 1.52-fold increased odds of survival compared to placebo.
- Statistical analysis (p=0.0247) and logistic regression (p=0.0283) confirmed a significant treatment effect on survival.
- Eleven percent more mice in the treatment group survived the toxic dose of (-)-propranolol HCl.
Conclusions:
- Administration of (R)-(+)-propranolol HCl homeopathic potency can counteract the toxicity of (-)-propranolol HCl in ICR mice.
- The findings support the potential of enantiomeric homeopathic preparations in mitigating drug-induced toxicity.
- (+)-propranolol HCl homeopathic potency demonstrated a protective effect against (-)-propranolol HCl toxicity in mice pre-treated with Rometar.
Related Concept Videos
Adrenergic Antagonists: Chemistry and Classification of β-Receptor Blockers
Adrenergic Antagonists: Pharmacological Actions of β-Receptor Blockers
Adrenergic Antagonists: ɑ and β-Receptor Blockers
Antihypertensive Drugs: Types of β-Blockers

