Related Experiment Video
Updated: Aug 14, 2026

Disrupting Reconsolidation of Fear Memory in Humans by a Noradrenergic β-Blocker
Published on: December 18, 2014
A comparison between atenolol and metoprolol in respect of central nervous system side effects
Abstract:
A double-blind crossover study was performed to compare the incidence of central nervous system (CNS) side effects with atenolol and metoprolol. Eleven women and 6 men who had previously developed such side effects on lipophilic beta-blockers were identified by means of a preliminary questionnaire. A 30-item psychiatric questionnaire was then used to detect changes in psychological status and possible CNS side effects. Discontinuation of the original lipophilic beta-blocker produced a significant improvement in quality of sleep, dreams, concentration, memory, energy and anxiety. Introduction of atenolol did not result in any significant CNS effects. With metoprolol, however, some effects occurred but not to the extent experienced prior to study on other more lipophilic beta-blockers. Blood pressure control was identical with both drugs.
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
Antiarrhythmic Drugs: Class II Agents as β-Adrenergic Blockers
Antianginal Drugs: Nitrates and β-Blockers
Organic nitrates, such as nitroglycerin, play a pivotal role. Once metabolized, they liberate nitric oxide, a molecular marvel. Nitric oxide triggers guanylyl cyclase and augments cGMP production. This biochemical cascade orchestrates the relaxation of vascular smooth muscles, ushering in vasodilation and enhancing coronary blood flow. Administered...
