Difference between Acute Stress and PTSD

The Temporal Criterion as a Differential Factor

The distinction between Acute Stress Disorder (ASD) and Post Traumatic Stress Disorder (PTSD) does not necessarily lie in the nature of the symptoms, which often overlap, but in the timing.

ASD is diagnosed when the symptomatology appears immediately after the event and persists from three days to a maximum of one month.

If symptoms (re-experiencing, avoidance, alertness) continue to be present beyond 30 days, the diagnosis evolves into PTSD.

It is vital to understand this timeline so as not to prematurely pathologize a normal adaptive reaction to an abnormal event.

The Expected Response vs. The Pathology

It is clinically expected, and even adaptive, for a person who has suffered an assault or serious accident to experience insomnia, fear, and intrusive memories for the first few weeks.

The nervous system is processing a life threat. ASD is considered an initial "shock" reaction.

Pathology sets in when the brain fails to integrate the experience and the alarm system remains chronically "on".

The transition from acute stress to PTSD implies that the natural recovery mechanisms have been blocked, preventing the memory from being filed as a past event and keeping it as a present threat.

Trajectories of Evolution: Recovery or Chronification

After the first critical month, there are two main paths: spontaneous recovery or chronification into PTSD.

Many individuals manage, with appropriate social support and their own resources, to reduce the intensity of symptoms to subclinical levels.

However, when avoidance is severe and cognitive interpretations of the event are very negative (guilt, vision of a totally dangerous world), recovery stalls.

The therapist should monitor this transition to intervene if the psychological "wound" does not show signs of natural healing after one month.

Summary

The main distinction is chronological. Acute Stress appears immediately and lasts up to one month; if symptoms persist beyond 30 days, the diagnosis evolves clinically into PTSD.

It is expected and adaptive to suffer initial symptoms while processing the threat. The pathology arises when the alarm system is blocked and remains chronically turned on, preventing the experience from being integrated.

After the first critical month, the evolution may move towards spontaneous recovery or chronification. Intervention is necessary if severe avoidance and negative interpretations stall natural healing.