Physiologic changes resulting from fear, play a major rôle in the persistence and intensification of the battle reaction. They increase irritability which results in exaggeration of the effects of both internal and external stimuli.Drug therapy in order to be successful must break this cycle. The patient is then better able to face memories of his traumatic experience and be unconditioned to them.Sedatives, by depressing the central nervous system and thereby producing sleep, are effective in shutting out external stimuli. This is curative in the fatigue state which predisposes to battle reaction, once it develops.Narcosynthesis not only reduces autonomic overactivity by depressing the hypothalamus, but promotes mental catharsis at the same time. The process of unconditioning the traumatic experience is therefore hastened. There are some drawbacks:1. It often causes the patient to go beyond the war experience, stirring up old neurotic conflicts which may merge with the war reaction, thereby adding to danger of chronicity.2. It can be administered continuously over only relatively short periods of time.Ergotamine interrupts the physiologic cycle of the battle reaction by neutralizing adrenalin liberated at the end organ. Desensitization to memories of the traumatic incident is hastened, because they can be discussed without the usual marked discomfort.