CNS-related side-effects with metoprolol and atenolol

Summary

Vivid and bizarre dreams, hallucinations, sleep disturbance and psychosis have all been described following treatment with β-Blockers. It has been suggested that these central nervous system (CNS) side-effects are related to the degree of lipophilicity of the β-blocker. A randomized double-blind crossover study was performed to compare the incidence of CNS side-effects with atenolol and metoprolol in hypertensive patients who had reported CNS side-effects with lipophilic β-Blockers. Eleven women and six men completed the study, in which a 30-item psychiatric questionnaire was used to detect changes in psychological status and possible CNS side-effects. Discontinuation of the original lipophilic β-blocker produced a significant improvement in quality of sleep, dreams, concentration, memory, energy, and anxiety. No significant CNS side-effects were reported with atenolol, but introduction of metoprolol caused a significant increase in the incidence of sleep disturbance (p<0.01) and restless nights (p<0.05), as well as failure to achieve satisfactory sexual intercourse (p<0.05). When compared with atenolol, metoprolol was associated with a significantly higher incidence of restless disturbed nights (p<0.05). Blood pressure control was identical for both β-Blockers. This study appears to confirm the association between CNS-related side-effects and the lipophilicity of β-Blockers.