EMDR Side Effects: What to Expect During and After Treatment

EMDR Side Effects Are Usually a Sign That Treatment Is Working

If you are considering EMDR therapy or have just started treatment, it is natural to wonder what side effects you might experience. Any therapy that reprocesses traumatic or distressing memories can temporarily activate your nervous system, and EMDR is no exception.

The good news: most EMDR side effects are mild, short-lived, and actually indicate that your brain is doing exactly what it is supposed to do — reorganizing distressing material into a more adaptive form. Understanding what is normal helps you stay the course instead of dropping out of treatment prematurely.

48-72 hours

Common Side Effects During and After EMDR Sessions

Not everyone experiences side effects, and their intensity varies from session to session. The following are the most frequently reported.

Vivid or Unusual Dreams

This is the single most common side effect reported after EMDR sessions. Because EMDR engages neurological processes related to REM sleep — the phase when your brain naturally consolidates and processes memories — it makes sense that dream activity often increases temporarily. Some people have vivid dreams related to the material they processed; others have dreams that seem completely unrelated but are unusually intense.

These dreams typically settle within two to three nights and do not require any intervention.

Heightened Emotional Intensity

You may feel more emotionally reactive than usual in the hours or days following a session. Things that normally would not bother you might bring tears, irritation, or a sense of vulnerability. This happens because reprocessing opens up emotional material that has been locked away, and your brain needs time to integrate it fully.

Fatigue and Mental Exhaustion

EMDR reprocessing is demanding cognitive work, even when a session feels relatively smooth. Many clients describe feeling "wiped out" afterward — similar to the exhaustion you feel after an intense workout, but mental rather than physical. Planning a lighter schedule on treatment days is wise.

Light-Headedness During Sessions

The bilateral stimulation used in EMDR — typically guided eye movements — can cause mild light-headedness or eye strain, especially during longer processing sets. This usually resolves within minutes of stopping the eye movements and is not medically concerning.

New Memories Surfacing

As your brain reprocesses one memory, it may spontaneously connect to related experiences you had not thought about in years. This is part of the Adaptive Information Processing model that underlies EMDR. These surfacing memories are not fabricated — they are existing memories that become accessible as the neural network activates. Your therapist will help you process them in subsequent sessions.

Temporary Increase in Distress

Some people experience a brief window — usually 24 to 48 hours — where their symptoms feel slightly worse before they feel better. Intrusive thoughts, emotional sensitivity, or body sensations related to the trauma may intensify temporarily. Clinicians sometimes call this a "processing wave," and it is well-documented in the EMDR literature.

~15-25%

Source: Shapiro, 2018

Less Common Side Effects

These occur in a smaller number of clients:

• Physical sensations such as tingling, warmth, tightness, or nausea — particularly in body areas associated with the stored trauma
• Difficulty sleeping the night after a session, or sleeping significantly more than usual
• Headache following a session, typically mild and responsive to normal remedies
• Feeling emotionally raw or vulnerable for several days rather than the typical one to two days

When Side Effects Are Normal vs. When to Contact Your Therapist

Myth-Busting: Common Fears About EMDR Safety

"Can EMDR Make You Worse?"

This is one of the most common fears, and it deserves an honest answer. In rare cases, people have reported feeling destabilized after EMDR — but this almost always occurs when the preparation phase was insufficient, the therapist moved too quickly into reprocessing, or the client had undiagnosed dissociative features that were not adequately assessed.

When EMDR is delivered by a properly trained therapist who follows the standard eight-phase protocol — including thorough history-taking and stabilization before any reprocessing begins — the risk of lasting negative effects is very low. Multiple meta-analyses have found EMDR to be as safe as or safer than other frontline trauma treatments like Prolonged Exposure and Cognitive Processing Therapy.

"Can EMDR Cause False Memories?"

This concern comes up regularly, and the evidence is reassuring. EMDR does not involve suggestion, guided imagery of events that may not have happened, or hypnotic techniques. Research published in the Journal of Experimental Psychology has found that EMDR does not increase susceptibility to false memories compared to other psychotherapy approaches.

What EMDR does do is help you access memories that were already stored but perhaps not easily retrievable. The memories that surface during reprocessing are your own — though the emotional charge attached to them may shift.

"Is EMDR Dangerous?"

EMDR is recognized as a safe and effective treatment by the World Health Organization, the American Psychological Association, the U.S. Department of Veterans Affairs, and the International Society for Traumatic Stress Studies. It has been studied in over 30 randomized controlled trials. No credible evidence suggests that EMDR is dangerous when administered appropriately.

That said, no therapy is risk-free. The temporary distress some people experience between sessions is real, and it is important that your therapist prepares you for this possibility and equips you with coping tools before reprocessing begins.

How the Preparation Phase Minimizes Risks

One of the most important features of the standard EMDR protocol is Phase 2: Preparation. During this phase, your therapist will:

1. Assess your stability. They will evaluate whether you have adequate coping resources and emotional regulation skills before beginning reprocessing.
2. Teach you self-regulation techniques. These may include the "Safe Place" visualization, container exercises, and grounding techniques you can use between sessions if distress increases.
3. Explain what to expect. Knowing that side effects are possible and normal reduces the likelihood that you will panic or drop out of treatment.
4. Establish a communication plan. Your therapist should tell you how to reach them between sessions if you experience unexpected distress.

Skipping or rushing this phase is the most common reason clients have difficult experiences with EMDR. If a therapist wants to begin reprocessing in your first or second session without adequate preparation, that is a red flag.

Contraindications: Who Should Be Cautious

EMDR is well-tolerated by most people, but certain conditions require extra care or may contraindicate treatment:

Discuss with your therapist before starting EMDR if you have:

• A dissociative disorder (such as Dissociative Identity Disorder) — stabilization work must come first
• Active psychosis or a thought disorder
• Uncontrolled seizure disorders (eye movements may be a concern in rare cases)
• Active substance dependence — sobriety or stabilization is typically needed first
• Significant self-harm behaviors that are not yet managed
• Certain neurological conditions affecting eye movement or visual processing

These are not absolute barriers to EMDR in every case, but they require a therapist with specialized training who can adapt the protocol appropriately.

How to Reduce Side Effects

Practical steps to minimize post-session effects:

1. Get adequate sleep the night before. A well-rested brain processes more efficiently.
2. Keep your post-session schedule light. Avoid demanding work, difficult conversations, or major decisions for the rest of the day.
3. Stay hydrated and eat after your session. Processing trauma is metabolically demanding.
4. Use your stabilization techniques. The skills your therapist taught you in Phase 2 exist for exactly this reason.
5. Limit alcohol and caffeine. Both can amplify anxiety and disrupt sleep during the processing window.
6. Journal if it helps. Some people find it useful to note what comes up between sessions. Others find that focusing on the material makes it more intrusive — follow what works for you.

The Bottom Line

EMDR side effects are real but rarely serious. Vivid dreams, emotional intensity, fatigue, and temporary increases in distress are the most common experiences, and they typically resolve within a few days. These effects are signs that your brain is actively reprocessing — which is the entire point of treatment.

The key to a safe EMDR experience is working with a properly trained therapist — you can search the EMDRIA therapist directory to find one — who follows the complete eight-phase protocol, does not rush through the preparation phase, and makes themselves available if you experience unexpected distress between sessions. When these conditions are met, EMDR is one of the safest and most effective trauma treatments available.

Have questions about EMDR side effects?

A qualified EMDR therapist can assess whether the treatment is appropriate for your situation and prepare you for what to expect.

Find a therapist