What are the side effects of EMDR and what happens after a session?

EMDR is not a gentle modality. It works by deliberately accessing traumatic memory networks — stored in what Shapiro (2001) calls "state-specific form" in the nervous system — and stimulating their reprocessing through bilateral stimulation. That process carries real costs, and understanding them is part of informed engagement with the work.

During and immediately after a session, the most common experience is a temporary escalation of disturbance before resolution. Shapiro is direct about this:

The emotional level can increase dramatically before the memory reaches an adaptive resolution. As long as the client is reporting a different level of emotion, either higher or lower, the information is assumed to be processing.

This means that a session can leave a person feeling worse before they feel better — more anxious, more raw, more exposed. Emotions may shift type as well as intensity: grief can become rage, numbness can open into sorrow. Physical sensations locked in the nervous system may resurface with unexpected force, sometimes felt in the specific body location where they were originally encoded. A client whose hand was burned as a child may feel that burning again during processing. These are not malfunctions; they are the information moving.

Incomplete processing is the more significant concern. When a session ends before a traumatic memory channel has been fully resolved — which happens regularly, given the time constraints of any clinical hour — the activated material does not simply go quiet. It continues to press. Shapiro notes that clients should be debriefed carefully about this, given tools for self-observation between sessions, and warned that new material may surface in dreams, intrusive imagery, or heightened emotional reactivity in daily life. The log and relaxation tape she recommends serve a specific function: they help the client observe emerging material rather than be consumed by it.

Abreaction — the reexperiencing of traumatic material at high intensity — is a normal potential part of EMDR processing, not a complication to be avoided at all costs. What makes it manageable is the dual focus the protocol maintains: the client holds awareness of both the past event and the present safety of the room. Without that dual consciousness, abreaction risks becoming retraumatization rather than reprocessing. Ogden (2006) makes a related point from the sensorimotor tradition: "abreaction or uncontrolled catharsis of overwhelming traumatic affects leads to states of hyperarousal and, at times, to complete psychological decompensation." The pacing discipline in EMDR — keeping arousal within what Ogden calls the "window of tolerance" — exists precisely to prevent this.

Dissociation is a specific risk with clients whose traumatic material is organized around dissociative defenses. Shapiro distinguishes EMDR abreaction from hypnotic abreaction on this point: properly conducted EMDR does not produce full flashbacks because the dual-focus structure keeps the client anchored in present time. But clients who tend to merge with past experience — who lose the "I'm here, not in Vietnam" orientation — require additional clinical attention and may need phase-one stabilization work before memory processing begins.

After a session, the responsible clinician assesses the client's capacity to leave the office safely, to drive, to manage whatever emotional material may continue processing in the hours that follow. This is not a formality. The reprocessing does not stop when the session ends. Dreams that night may carry the activated material. Ordinary triggers — a smell, a sound, a posture — may suddenly carry more charge than usual. This is the system continuing its work, not evidence that something has gone wrong.

What the clinical literature does not say — and what is worth naming — is that EMDR's framing of all this as "information processing moving toward adaptive resolution" carries its own implicit promise: that the suffering is temporary, that the system is self-healing, that the endpoint is integration and freedom. Shapiro's volunteer Sadie, described in Clayton (2025), reports feeling "liberated" and "free" after a session in which her eating disorder's entire holding function became visible and released. These outcomes are real. They are also not guaranteed, and the gap between the protocol's optimism and any particular person's actual experience is where the real clinical work lives.

  • James Hillman — portrait of the archetypal psychologist whose work on descent and the soul's suffering offers a counterpoint to resolution-oriented frameworks
  • Shadow — the Jungian concept most relevant to what EMDR surfaces: the material the ego has refused to carry
  • Nigredo — the alchemical stage of blackening and dissolution that depth psychology reads as the necessary precondition for transformation
  • Find a depth-oriented therapist — practitioners trained to hold the complexity that trauma work opens

Sources Cited

  • Shapiro, Francine, 2001, Eye Movement Desensitization and Reprocessing (EMDR): Basic Principles, Protocols, and Procedures
  • Ogden, Pat, 2006, Trauma and the Body: A Sensorimotor Approach to Psychotherapy
  • Clayton, Ingrid, 2025, Fawning: Why the Need to Please Makes Us Lose Ourselves — and How to Find Our Way Back