Chronic dosing with mirtazapine does not produce sedation in rats

Objective: Sedation/somnolence are major side effects of pharmacotherapies for depression, and negatively affect long-term treatment compliance in depressed patients. Use of mirtazapine (MIR), an atypical antidepressant approved for the treatment of moderate to severe depression with comorbid anxiety disorders, is associated with significant sedation/somnolence, especially in short-term therapy. Nonetheless, studies with human subjects suggest that MIR-induced sedation is transient, especially when high and repeated doses are used. The purpose of this study was to explore the effects of acute and chronic administration of different doses of MIR on sedation in the rat. Methods: Assessment of sedation was carried out behaviorally using the rotarod, spontaneous locomotor activity, and fixed-bar tests. Results: A 15-mg/kg dose of MIR induced sedative effects for up to 60 minutes, whereas 30 mg/kg or more produced sedation within minutes and only in the first few days of administration. Conclusion: These results suggest that 30 mg/kg is a safe, well-tolerated dose of MIR which generates only temporary sedative effects.

[Study the effect of buspirone and trazodone on hematological damage induced by long-term exposure to noise in mice]

The study investigated the effect of stress induced by long-term exposure to noise on body immunity through total white blood cell and lymphatic cell count, and on neutrophil-to-lymphatic cell ratio as a physiological marker of noise-induced stress in rats. In addition, the effect of both buspirone and trazodone in alleviating this negative outcome induced by noise was also investigated on 32 rats aged 90-100 days at the beginning of the study period. Results of the study was consistent with previous theories that noise may be considered as a causative agent which influences body's immune system when it reduces both total white blood cell and lymphatic cell count. Results also showed that the ration of neutrophil-to-lymphatic cell was increased as a result of long-term exposure to noise. Furthermore, the study presented a new evidence of antagonizing and therapeutic effect of buspirone and trazodone to stress-induced physiological damage

Trazodona: farmacologia e interações medicamentosas / Trazodone: pharmacology and drug interactions

CONTEXTO: A trazodona, substância com potencial antidepressivo e ansiolítico, continua sendo uma opção terapêutica, inclusive como indutor do sono. OBJETIVO: Recuperar informações e buscar novos conhecimentos sobre sua farmacocinética e sua farmacodinâmica e, assim, melhor compreender seu perfil de interações medicamentosas, aumentando a segurança em seu uso. MÉTODO: Esta revisão foi realizada por meio de busca eletrônica nos bancos de dados Medline e HighWire Press, utilizando como palavras-chave "trazodone", "adverse drug reaction" e "drug interaction". Eventualmente, informações complementares foram extraídas de bibliografia pesquisada e de livros-texto de farmacologia. RESULTADOS: Foram encontradas importantes informações sobre os perfis farmacocinético e farmacodinâmico da trazodona, mostrando o interesse mantido de pesquisadores. CONCLUSÕES: A trazodona tem se renovado como uma opção não apenas em depressão e insônia, mas também em certas disfunções sexuais, demonstrando um padrão de interações favorável e um perfil de reações adversas que pode ser contornado se bem avaliado e conduzido.

BACKGROUND: Trazodone is an atypical antidepressant with further therapeutic effects on anxiety and sleep disorders. OBJECTIVE: To review the pharmacokinetic and pharmacodynamic properties of trazodone in order to better understand the potential of adverse events related to drug interactions. METHODS: Electronic search of Medline and High Wire Press databases using the keywords: "trazodone", "adverse drug reaction", and "drug interaction". Additional references were obtained from pharmacology textbooks. RESULTS: A comprehensive data set on the pharmacological profile of trazodone was obtained. CONCLUSION: Trazodone is being increasedly prescribed no only to depressive and sleep disorders, but also in certain sexual dysfunctions. The risk of adverse events due to drug interactions is acceptable and manageable, rendering trazodone a useful tool in the treatment of psychiatric and related disorders.