Teixeira Marcus Zulian
Department of Clinical Medicine, Faculty of Medicine, Universidade de São Paulo, São Paulo, Brazil.
Homeopathy. 2009 Apr;98(2):114-21. doi: 10.1016/j.homp.2009.02.004.
Samuel Hahnemann noticed that palliative treatments for the symptoms of chronic diseases, after an initial improvement, provoked symptoms similar but stronger symptoms to those initially suppressed. He regarded this as a consequence of the vital reaction of the organism: an automatic and instinctive capacity to return to the initial health condition altered by medicines. Using this homeostatic conception of the organism as a treatment rationale, Hahnemann proposed the therapy of similarity, administering to the patients medicines capable of causing, in healthy individuals, similar symptoms to the natural disease. Based on experimental observations, he proposed that the primary action of the drug was followed by the secondary and opposite action of the organism, inaugurating homeopathic pharmacology, and alerting to the harmful consequences of palliative medicines in susceptible individuals. Such iatrogenic events can be observed in contemporary medicine, after the withdrawal of modern enantiopathic medicines, according to the study of the rebound effect or paradoxical reaction of the organism.
This study reviews the recent studies which describe suicidality after the suspension or discontinuation of second generation antidepressants according to the hypothesis of the paradoxical reaction of the organism.
Rebound and withdrawal effects, including suicidality occur with antidepressant drugs. They are relatively rare but more intense than the primary action of the drug. The probability of such effects is influenced by patient factors including age and diagnosis, and drug factors including half-life.
塞缪尔·哈内曼注意到，对慢性病症状的姑息治疗在最初改善后，会引发与最初被抑制症状相似但更强烈的症状。他认为这是机体生命反应的结果：机体具有自动且本能地恢复因药物而改变的初始健康状态的能力。哈内曼以这种机体的稳态概念作为治疗原理，提出了相似性疗法，即给患者服用在健康个体中能引发与自然疾病相似症状的药物。基于实验观察，他提出药物的主要作用之后会伴随机体的次要且相反的作用，开创了顺势疗法药理学，并警示了姑息性药物对易感个体的有害后果。根据对机体反跳效应或矛盾反应的研究，在当代医学中，停用现代对抗疗法药物后也能观察到此类医源性事件。
本研究根据机体矛盾反应假说，回顾了近期描述第二代抗抑郁药停药或中止后自杀倾向的研究。
抗抑郁药物会出现反跳和撤药效应，包括自杀倾向。这些效应相对罕见，但比药物的主要作用更强烈。此类效应的发生概率受患者因素（包括年龄和诊断）以及药物因素（包括半衰期）的影响。
