EMDR Side Effects: What to Expect Between Sessions

EMDR therapy is one of the most effective treatments for trauma and PTSD, and most adults tolerate it well. But the 24 to 72 hours between sessions can bring temporary side effects as your brain continues to process what was activated in the room. The most common are vivid dreams, emotional waves, fatigue, new memories or images surfacing, mild headaches, and increased awareness of body sensations. None of these mean something is wrong — they usually mean the work is doing what it is supposed to do. This guide explains why these reactions happen, how long they typically last, what is normal, what is not, and what you can do between sessions to support your nervous system. It is grounded in current guidance from the VA National Center for PTSD, the APA Clinical Practice Guideline, and the EMDR International Association.

Why EMDR has side effects in the first place

EMDR — short for Eye Movement Desensitization and Reprocessing — is a structured, eight-phase trauma therapy. The EMDR International Association describes those phases as “initial history discovery and treatment planning, preparation, assessment, desensitization, installation, body scan, closure, and reevaluation.” During the active processing phases, your therapist guides you through brief, focused attention on a target memory while you also follow a back-and-forth eye movement, tapping, or alternating tone — what clinicians call bilateral stimulation.

That combination — focused attention on the memory plus rhythmic side-to-side input — appears to help the brain reconsolidate the memory in a less distressing form. Unlike exposure-based therapies, EMDR does not require talking in detail about the distressing event or completing homework. That is one of the reasons many people find it easier to engage with than other trauma treatments. PTSD affects about 3.6 percent of U.S. adults in any given year, per NIMH, and EMDR is one of the established options for treating it.

But “no homework” does not mean nothing happens between sessions. EMDRIA notes that during the closure phase, clients are “briefed on what to expect between sessions (some processing may continue, some new material may arise).” That is the source of most EMDR side effects. Your nervous system has been activated in session, and it keeps working on what came up for the next day or two.

Think of it this way: a session opens a door to a particular memory network. Closing that door at the end of the hour does not unactivate the network instantly. For the next 24 to 72 hours, your brain is still organizing and integrating. Dreams change. Old images may briefly surface. You might feel weepy at a song that never used to move you. This is not a side effect in the medication sense — it is the work continuing in the background.

Cleveland Clinic frames the safety profile plainly: “EMDR has very low risks,” with most clients experiencing only mild and temporary reactions between sessions. The point of knowing what those reactions look like in advance is so you do not panic when one shows up.

The 6 most common temporary EMDR side effects

These are the reactions our clinicians hear about most often during EMDR treatment. The list is not exhaustive, and not every client experiences every one. If something on this list shows up after a session, you are in good company — and you are not doing EMDR wrong.

Vivid dreams or unusual dream activity

This is the most commonly reported between-session experience. Dreams may feel more intense, more visual, more emotionally charged, or thematically tied to what came up in session. Sometimes the connection is direct — a dream that references the memory you targeted that day. More often it is indirect — a dream with a feeling tone that echoes the work.

Why it happens: REM sleep and EMDR may share processing mechanisms. The eye movements in EMDR resemble those of dreaming sleep, and both appear to help the brain consolidate emotional memory.

What is normal: more vivid dreams, dreams you remember, dreams on session themes — for one to three nights. What is worth telling your therapist: nightmares that wake you repeatedly, dreams that leave you feeling unsafe the next day, or sleep disruption lasting more than a few nights.

Emotional waves — feeling weepy, irritable, or “raw” for a day or two

Many clients describe the day after EMDR as emotionally porous. You may cry at a commercial. You may snap at your partner. You may feel everything slightly more — the joy as well as the sadness. This is not regression. It is your emotional bandwidth widening as the protective numbing around a memory thins.

Some people prefer to schedule EMDR sessions on days when they can come home to a quiet evening rather than a high-stakes meeting. That is a reasonable accommodation, not a sign of fragility. The VA notes that during EMDR “you may feel uncomfortable when focusing on trauma-related memories or beliefs,” and that “these feelings are usually brief, and people tend to feel better as they keep doing EMDR.” This pattern shows up across populations — service members in our EMDR for veterans program describe a similar rhythm of intensity followed by relief.

Tell your therapist if the emotional intensity does not settle within 48 to 72 hours, or if you find yourself avoiding people or responsibilities you would normally meet.

Fatigue or unusual tiredness

Trauma processing is metabolic work. Many clients describe a deep tiredness in the evening after EMDR — the kind that is more about needing to rest than needing more sleep. Some also sleep more deeply or longer that night.

This is your nervous system asking for downshift. Honor it when you can. A session is not the day for a long workout, a difficult conversation, or hours of screen time. Plan a softer landing — a walk, a meal, an early bedtime.

New memories or images surfacing unexpectedly

EMDR works on memory networks, not isolated single memories. When you process one node in a network, related memories sometimes surface — a sound, an image, a brief flashback to something you had not consciously thought about in years. Most are brief and not destabilizing.

This is also the source of one of EMDR’s most surprising effects: clients sometimes recover memory fragments that feel new. Treat these with curiosity rather than urgency. Write them down. Bring them to your next session. Your therapist will help you decide whether they belong in the current target plan or are something to hold for later.

What is not normal: a recovered memory that triggers a sense of imminent danger, dissociation that lasts more than an hour, or any image that pulls you back into the original event in a way you cannot interrupt. Those warrant a call to your therapist before your next scheduled session.

Mild headaches or muscle tension

A subset of clients report mild headaches in the hours after a session, or sore neck and jaw muscles. The eye-movement work itself can fatigue the small muscles around the eyes; clinicians often switch to tactile bilateral stimulation for clients prone to this. Tension headaches can also come from the body holding still through emotionally activating content.

What helps: water, a warm shower, light stretching, and sleep. What warrants a call: a headache that is severe, sudden in onset, or accompanied by visual disturbance, neurological symptoms, or vomiting. Those are not EMDR side effects — they are reasons to seek medical evaluation.

Increased awareness of body sensations

One of EMDR’s protocol phases is the “body scan.” Trauma often lives in the body as much as in the mind, and the body scan asks you to notice where activation still sits — chest, throat, gut, shoulders. That awareness can stay heightened for a day or two. You may notice your heart rate more, feel your breath catch, register tension you had been ignoring.

This is generally a good sign — interoception is part of recovery from trauma. But for clients with panic disorder or somatic-symptom presentations, heightened body awareness can briefly amplify symptoms. If that is your history, tell your therapist before treatment starts so they can pace accordingly.

How long EMDR side effects last (and what is normal vs not)

The typical EMDR side effect resolves within 24 to 72 hours of a session. By the time you are sitting down for your next appointment a week later, most clients feel back to baseline — often a calmer baseline than the one they walked in with the week before.

The pattern is not linear. Some sessions barely register between-session effects. Others — usually the sessions that touched a particularly loaded memory — produce three days of dreams, fatigue, and emotional waves. Both patterns are within the normal range. The APA’s clinical practice guideline notes that in EMDR, “processing of a specific memory is generally completed within one to three sessions,” so the heavier between-session reactions tend to cluster around the sessions where the most active work is happening.

Normal — does not require a call to your therapist:

• Vivid dreams for one to three nights
• Emotional sensitivity for 24 to 48 hours
• Fatigue the evening after a session
• Brief new images or memories that pass within a day
• Mild headache, mild muscle tension
• A few hours of heightened body awareness

Worth a check-in with your therapist before the next session:

• Dreams or images that wake you nightly for more than three days
• Emotional waves that do not settle within 72 hours
• Avoidance of people, work, or responsibilities you would normally meet
• Increased substance use to manage between-session feelings
• A new memory that feels too big to hold until next session
• Significant sleep disruption

Warrants immediate care — call your therapist today, and if you cannot reach them, go to a higher level of care:

• Suicidal thoughts or plans
• Dissociation lasting more than an hour (feeling unreal, outside your body, disconnected from your surroundings)
• Hallucinations or psychotic-like experiences
• Inability to function or care for yourself or dependents
• A flashback that feels like the original event is happening now and you cannot ground out of it

If you are in crisis, the 988 Suicide and Crisis Lifeline is available 24 hours a day, every day of the year. You can call or text 988. If you or someone with you is in immediate danger, call 911.

EMDR is generally a safe, well-tolerated treatment when delivered by a trained clinician — but no trauma therapy is risk-free, and the criteria above exist so you can advocate for yourself if something does not feel right.

What to do between EMDR sessions to support processing

You do not need to “do” EMDR between sessions — there is no homework in the traditional sense. But there are simple ways to make space for your nervous system to do its work without getting in its way.

Sleep. Trauma processing happens during sleep. Aim for your normal hours plus a little more. Prioritize wind-down — no screens for the last hour, dim lights, a regular bedtime.

Hydrate. Dehydration amplifies headache and fatigue.

Journal lightly. EMDRIA encourages clients to “keep a journal to record these experiences” between sessions — not to analyze them, but to capture them so you can bring them to your next appointment. A line or two is enough.

Use the grounding skills your therapist taught you. The container exercise, the safe-place visualization, 5-4-3-2-1 sensory grounding — these are not just for crisis moments. Use them daily for a few minutes to keep your window of tolerance wide.

Skip alcohol and cannabis for at least 24 hours after a session. Both substances interfere with REM sleep, when much of the integration happens. They can also dampen emotional waves in ways that look helpful but actually delay processing.

Move gently. A walk, light yoga, stretching — not a high-intensity workout the same day. Movement helps discharge activation; intensity can overstimulate a system already working hard.

Anchor your senses. A familiar playlist, a known smell, a piece of clothing that feels safe. Sensory anchors signal “you are here, you are safe” to a nervous system that has been time-traveling.

Tell someone what you are doing. A partner, a friend, a trusted family member — not the session details, just the fact that you are in trauma work and the next day or two might be tender.

When to call your EMDR therapist

The standard EMDR contract assumes you will see your therapist weekly and discuss between-session experiences then. But there are situations where you should not wait.

Call your therapist before your next session if:

• You are having suicidal thoughts, even passive ones
• A new memory has surfaced that feels destabilizing
• You are dissociating for more than an hour at a time
• You have not slept for more than 48 hours
• You are using more alcohol, cannabis, or other substances than is typical for you
• You are avoiding work, school, or relationships in a way that is starting to have real-world consequences
• Your symptoms have intensified in a way that feels different from “this will pass in a day”

Most EMDR therapists return a call within the same day. If yours does not, or the situation is acute, call 988, go to an emergency department, or contact your primary care provider for a same-day appointment.

If you are in Thrive’s virtual IOP, you have access to a clinical team beyond your individual therapist, including same-day check-in availability. That is part of why intensive outpatient is a strong container for EMDR work — you are never processing alone.

Common questions about EMDR side effects

Are EMDR side effects dangerous?

In almost all cases, no. Cleveland Clinic describes EMDR as having “very low risks,” and the most common between-session reactions are mild and temporary — dreams, emotional waves, fatigue. The exceptions are clients with a history of psychosis, severe dissociative disorders, or active suicidality, who need careful clinical screening before starting EMDR. A trained EMDR therapist will assess for these before treatment begins.

How long do EMDR side effects usually last?

Most between-session side effects resolve within 24 to 72 hours. By the time you are sitting down for your next weekly session, you are typically back to baseline. Sessions that touch heavier material can produce three days of more intense reactions; this is still within the normal range. Anything lasting more than four to five days warrants a conversation with your therapist.

Can EMDR make my symptoms worse?

A temporary increase in symptoms in the days right after a session is common and usually part of the processing — not a sign that EMDR is failing. A sustained increase over multiple weeks is different and worth discussing with your therapist. They may slow the pace, return to stabilization work, or add resources. For a deeper look at when EMDR may not be the right fit, see our guide to the potential risks of EMDR therapy.

Should I drink alcohol between EMDR sessions?

We recommend avoiding alcohol and cannabis for at least 24 hours after each session, and ideally limiting use throughout the course of treatment. Both substances suppress REM sleep, which is when much of the trauma integration appears to happen. They also dampen the emotional waves that are part of the processing — which can feel helpful in the moment but tends to push the work into the next session rather than completing it.

Do EMDR side effects mean EMDR is working?

Not reliably, either way. Some clients have very few between-session reactions and still make meaningful progress. Others have vivid dreams for weeks and also do well. Better markers: lower distress when the target memory comes up, more flexible body responses to triggers, fewer intrusive symptoms over time, and a sense that the memory feels more like the past than the present. Your therapist measures these during the assessment and reevaluation phases.

When should I call my therapist about side effects?

Call before your next session if you experience suicidal thoughts, dissociation lasting more than an hour, hallucinations, a destabilizing new memory, severe sleep disruption beyond two nights, or a noticeable increase in substance use. For symptoms that fall short of those — vivid dreams, emotional sensitivity, fatigue, brief new images — it is fine to wait and discuss them at your next scheduled appointment.

Next steps

If you are considering EMDR for trauma or PTSD, knowing what to expect between sessions is part of the work. Thrive’s virtual IOP integrates EMDR with skills-based support so you are never processing alone. Get started with Thrive — free, confidential insurance verification. If you are in crisis, the 988 Suicide and Crisis Lifeline is available 24/7.