Dissociative Amnesia (ICD-11: 6B61): Complete Coding and Diagnostic Guide

1. Introduction

Dissociative amnesia represents one of the most intriguing and clinically relevant dissociative disorders in contemporary medical practice. It is characterized by a sudden and significant inability to recall important autobiographical memories, particularly those related to traumatic or extremely stressful events, which cannot be explained by common forgetfulness or normal physiological processes.

This disorder fundamentally differs from other forms of amnesia by its psychogenic origin and by the selective nature of the affected memories. While memory for general information and procedural skills remains intact, significant personal recollections become inaccessible to consciousness, creating gaps in the individual's autobiographical narrative.

The prevalence of dissociative amnesia varies considerably depending on the population context studied. It is more common in environments where there is greater exposure to trauma, including conflict zones, areas with high incidence of interpersonal violence, and communities affected by natural disasters. Clinical studies indicate that the disorder is frequently underdiagnosed, as many patients do not seek specific care for their amnestic symptoms or these are incorrectly attributed to other medical conditions.

The importance of correct coding of this disorder is critical for multiple aspects of health care. Appropriate coding enables precise epidemiological tracking, facilitates research on effective treatments, ensures appropriate reimbursement of services provided, and guarantees that patients receive specific therapeutic interventions. Furthermore, correct documentation is essential for medico-legal purposes, especially in cases involving trauma or victimization.

2. Correct ICD-11 Code

Code: 6B61

Description: Dissociative amnesia

Parent category: Dissociative disorders

Official definition: Dissociative amnesia is characterized by an inability to recall important autobiographical memories, typically of recent traumatic or stressful events, that is inconsistent with ordinary forgetting. The amnesia does not occur exclusively during another dissociative disorder and is not better explained by another mental, behavioral, or neurodevelopmental disorder. The amnesia is not due to the direct effects of a substance or medication on the central nervous system, including withdrawal effects, and is not due to a disease of the nervous system or traumatic brain injury. The amnesia results in significant impairment in personal, family, social, educational, occupational, or other important areas of functioning.

This code belongs to the chapter on Mental, Behavioral, and Neurodevelopmental Disorders of ICD-11, specifically within the section on dissociative disorders. The hierarchical structure of ICD-11 allows for greater diagnostic specificity and facilitates differentiation among various types of amnesia, whether of organic origin, substance-induced, or dissociative in nature.

Coding with 6B61 requires robust clinical documentation that clearly demonstrates the dissociative nature of the amnesia, its temporal relationship with stressful or traumatic events, and the exclusion of organic causes through appropriate medical evaluation.

3. When to Use This Code

Code 6B61 should be used in specific clinical scenarios that meet the established diagnostic criteria. Here are detailed practical situations:

Scenario 1: Acute post-traumatic amnesia A patient presents to the emergency department after being a victim of violent assault. In the subsequent days, he demonstrates complete inability to recall the traumatic event and the hours immediately before and after the incident. Neurological evaluation, including neuroimaging, reveals no structural lesions. The patient maintains intact memory for other events in his life and does not present general cognitive deficits. This is a typical case for coding 6B61.

Scenario 2: Localized amnesia following domestic violence A woman seeks psychiatric care reporting specific periods of "lost time" that coincide with episodes of severe intimate partner violence. She is able to clearly recall events before and after, but presents amnestic gaps circumscribed to periods of abuse. Medical evaluation rules out organic causes, and there is no substance use. Code 6B61 is appropriate in this context.

Scenario 3: Selective amnesia in disaster survivor A survivor of a large-scale accident is able to recall some aspects of the traumatic event, but presents amnesia for specific elements that are particularly distressing, such as the sight of fatalities or moments of extreme personal danger. Memory for other aspects of life remains preserved. This pattern of selective amnesia justifies the use of code 6B61.

Scenario 4: Generalized amnesia with sudden onset A patient is found disoriented in a public place, unable to recall his identity, personal history, or any autobiographical information. Complete medical investigation, including laboratory and imaging tests, does not identify organic causes. Collateral history reveals that the patient was under extreme stress related to significant financial and family losses. This presentation of generalized amnesia of dissociative nature is coded as 6B61.

Scenario 5: Continuous amnesia following specific traumatic event An emergency professional develops inability to form new autobiographical memories after responding to a particularly traumatic incident involving children. Neuropsychological evaluation demonstrates preserved cognitive capacity for other functions, and medical investigation excludes organic causes. This less common pattern of dissociative amnesia is also coded with 6B61.

Scenario 6: Dissociative amnesia with partial recovery A combat veteran presents significant memory gaps for specific periods of active service in a conflict zone. Over the course of psychotherapeutic treatment, some memories begin to return in fragmented form. The dissociative nature of the amnesia, its link to trauma, and the absence of organic causes justify code 6B61.

4. When NOT to Use This Code

It is essential to recognize situations in which code 6B61 is not appropriate, directing toward more precise alternative coding:

Specific exclusions with alternative codes:

If the patient presents amnesia clearly related to excessive alcohol consumption, with a pattern of alcoholic blackouts and history of dependence, use code 6B70.7871 - Amnestic disorder due to alcohol use. The differentiation is based on the direct causal relationship with the substance and the temporal pattern of consumption.

When amnesia is characterized primarily by the inability to form new memories after the onset of the disorder, without evident dissociative component, the appropriate code is MB23.1240 - Anterograde amnesia. This condition generally has organic etiology.

If the patient presents loss of memories prior to a specific event, but with demonstrable neurological etiology, use MB23.1789 - Retrograde amnesia. The crucial differentiation is the presence of identifiable organic substrate.

For cases where amnesia is documented but without sufficient specification for more precise classification, and without clear dissociative characteristics, use MB23.Z - Amnesia NOS (not otherwise specified).

When amnesia results from organic brain damage unrelated to alcohol, such as encephalitis, cerebral hypoxia, or structural lesions, the correct code is 6D72.859 - Non-alcoholic organic amnestic syndrome.

In patients with epilepsy who present periods of confusion and amnesia after seizures, use 8A61.88146 - Post-ictal amnesia in epilepsy. This is a direct consequence of epileptic activity.

Other important exclusions:

Do not use 6B61 when amnesia occurs exclusively in the context of another more comprehensive dissociative disorder, such as dissociative identity disorder, where amnesia is only one component of a more complex clinical presentation.

Avoid this code when there is clear evidence of malingering or intentional production of symptoms for secondary gain, situations that require appropriate coding within factitious disorders.

Do not apply 6B61 in cases of benign age-related forgetfulness, distraction, or common memory failures that do not reach the threshold of significant functional impairment.

5. Step-by-Step Coding Process

Step 1: Assess diagnostic criteria

Diagnostic confirmation of dissociative amnesia requires systematic and comprehensive evaluation. Begin with detailed clinical interview exploring the nature, extent, and temporal pattern of memory loss. Utilize structured instruments such as the Structured Clinical Interview for Dissociative Disorders (SCID-D) when available.

Document specifically which memories were lost, when the amnesia began, and whether there is temporal relationship with stressful or traumatic events. Assess the level of functioning before and after amnesia onset to establish significant functional impairment.

Perform neuropsychological evaluation to characterize the memory profile, distinguishing between autobiographical memory (affected in dissociative amnesia) and other types of memory (usually preserved). This evaluation helps differentiate dissociative from organic causes.

Request complete medical evaluation including neurological examination, basic laboratory tests (complete blood count, renal function, hepatic function, thyroid function, vitamin B12) and neuroimaging when indicated, to exclude organic causes of amnesia.

Step 2: Verify specifiers

ICD-11 recognizes two main specifiers for dissociative amnesia that should be documented:

6B61.0 - Dissociative amnesia with dissociative fugue: Use when amnesia is accompanied by apparently purposeful travel or wandering, with confusion about personal identity or assumption of new identity.

6B61.Z - Dissociative amnesia, unspecified: When there is no dissociative fugue or when information is insufficient for further specification.

Also document additional clinical features such as temporal extent of amnesia (localized, selective, generalized, or continuous), symptom duration, and onset pattern (sudden versus gradual).

Step 3: Differentiate from other codes

Differentiation from 6B60 - Dissociative neurological symptom disorder: This code is used for neurological symptoms such as paralysis, blindness, or seizures of dissociative nature. The key difference is that 6B61 focuses exclusively on amnesia for autobiographical memories, while 6B60 encompasses motor, sensory, or cognitive symptoms that are not primarily amnestic.

Differentiation from 6B62 - Trance disorder: Trance disorder involves temporary alteration of state of consciousness with loss of usual sense of personal identity, but without assumption of alternative identity. The main difference is that in 6B62 the focus is on the altered state of consciousness during the trance, not on subsequent amnesia as primary manifestation.

Differentiation from 6B63 - Trance and possession disorder: This disorder is characterized by episodes in which the person is possessed by an external entity (spirit, deity) with distinct behaviors and identity. Although there may be amnesia for possession episodes, the primary diagnosis is possession disorder when this is the dominant presentation, reserving 6B61 for cases where amnesia is the central manifestation without possession phenomena.

Step 4: Required documentation

Checklist of mandatory information:

• Detailed description of lost memories (type, period, content)
• Date and circumstances of amnesia onset
• Temporal relationship with stressful or traumatic events
• Duration of amnestic symptoms
• Pattern of amnesia (localized, selective, generalized, continuous)
• Assessment of functional impairment in specific life areas
• Results of medical/neurological evaluation to exclude organic causes
• Screening for substance use and medications
• History of other mental disorders
• Presence or absence of dissociative fugue
• Response to therapeutic interventions

Appropriate medical record documentation: Use clear and objective language describing observed and reported symptoms. Document the diagnostic reasoning explaining why alternative causes were ruled out. Record the specific ICD-11 criteria that were met. Maintain follow-up documentation regarding symptom progression and treatment response.

6. Complete Practical Example

Clinical Case:

A 32-year-old female patient, a teacher, presents to psychiatric consultation accompanied by a family member, reporting "memory loss" that is preventing her from working. According to collateral information, three weeks ago the patient was a victim of a flash kidnapping that lasted approximately four hours, during which she was threatened with a firearm and verbally assaulted.

Since the event, the patient cannot recall any detail of the kidnapping, including the perpetrators' faces, the location where she was held, or how she was released. Curiously, she also cannot recall events from the 24 hours prior to the kidnapping, a period that included her daughter's birthday. She has clear memory for events following her release.

The patient reports that the amnesia is causing significant distress, as authorities have requested her statement and she feels unable to assist in the investigation. Additionally, she has developed intense fear of leaving home, experiences frequent nightmares (although she cannot recall the content upon waking), and concentration difficulties that prevent her from preparing lessons.

On mental status examination, the patient is alert, oriented to time, place, and person (except for the amnestic period), with coherent and organized speech. She denies alcohol or other substance use. She denies prior psychiatric history. Physical and neurological examination reveals no abnormalities. Cranial computed tomography performed in the emergency department following the event was normal.

Neuropsychological evaluation demonstrates preserved general cognitive functions, including attention, working memory, semantic memory, and procedural memory. She demonstrates significantly reduced performance only on autobiographical memory tests for the specific period in question.

Step-by-Step Coding:

Criteria Analysis:

1. Inability to recall important autobiographical memories: Confirmed - patient cannot recall significant traumatic event (kidnapping) or the immediately preceding period.

2. Typically of traumatic or stressful events: Confirmed - kidnapping with threat to life constitutes a severe traumatic event.

3. Inconsistent with ordinary forgetting: Confirmed - it is not normal to completely forget such a significant and emotionally charged event.

4. Does not occur exclusively during another dissociative disorder: Confirmed - no evidence of dissociative identity disorder, depersonalization-derealization disorder, or other dissociative disorders.

5. Not better explained by another mental disorder: Confirmed - although there are symptoms of post-traumatic stress, the amnesia is disproportionate and constitutes the primary manifestation.

6. Not due to substances: Confirmed - patient denies substance use, and toxicology was negative.

7. Not due to disease of the nervous system or traumatic brain injury: Confirmed - neurological evaluation and neuroimaging normal, with no evidence of brain injury.

8. Results in significant impairment: Confirmed - inability to work, psychological distress, documented functional limitation.

Code selected: 6B61 - Dissociative amnesia

Complete justification:

The case meets all diagnostic criteria for dissociative amnesia. The localized amnesia (circumscribed to the period of trauma and preceding hours) emerged temporally related to a severe traumatic event. Medical evaluation excluded organic causes, including traumatic brain injury, substance effects, and neurological diseases. The selective nature of the amnesia (preservation of other autobiographical memories and cognitive functions) is characteristic of a dissociative process. Functional impairment is evident in the inability to return to work and social limitations.

There is no associated dissociative fugue, therefore the appropriate specifier would be 6B61.Z (unspecified) or simply 6B61 if the system does not require a specifier.

Applicable complementary codes:

• 6B40 - Post-traumatic stress disorder (as an additional diagnosis for symptoms of reexperiencing, avoidance, and hyperarousal)
• QE85 - Exposure to threat to life (context code to document the traumatic event)

7. Related Codes and Differentiation

Within the Same Category:

6B60: Dissociative neurological symptom disorder

When to use 6B60: Use this code when the patient presents with neurological symptoms such as weakness, paralysis, abnormal movements, difficulty swallowing, sensory symptoms (blindness, deafness, loss of sensation) or seizure-like episodes that cannot be explained by known neurological conditions and have a dissociative origin.

When to use 6B61: Use for specific amnesia of autobiographical memories without other prominent neurological symptoms.

Main difference: 6B60 focuses on motor, sensory, or seizure-like alterations of consciousness, while 6B61 is specific for loss of autobiographical memory. A patient may have both diagnoses if presenting with both amnesia and dissociative neurological symptoms.

6B62: Trance disorder

When to use 6B62: Appropriate for episodes of temporary alteration of consciousness characterized by loss of sense of personal identity and reduced awareness of the environment, with stereotyped behaviors experienced as beyond control. Common in specific cultural or religious contexts.

When to use 6B61: For persistent amnesia of autobiographical memories outside the context of trance states.

Main difference: 6B62 involves episodic altered states of consciousness with specific characteristics during trance, while 6B61 refers to amnesia as the primary and persistent manifestation. If there is amnesia only for trance episodes, consider 6B62 as the primary diagnosis.

6B63: Trance and possession disorder

When to use 6B63: When the individual experiences episodes in which their identity is replaced by a possession identity (spirit, deity, demon, another person), with distinct behaviors, memories, and perceptions, usually with amnesia for the episodes.

When to use 6B61: For dissociative amnesia that does not involve possession phenomena or assumption of alternative identities.

Main difference: 6B63 is characterized by the experience of possession by an external entity with a distinct identity and behaviors characteristic of that identity, while 6B61 is amnesia without possession phenomena. Amnesia in 6B63 is for the possession episodes, while in 6B61 it is for traumatic or stressful events experienced in the habitual identity.

Differential Diagnoses:

Dissociative identity disorder: Presents with two or more distinct identities with their own patterns of perception and relationship. Although it includes amnesia, this is only one component of a more complex presentation. If there are clearly distinct alternative identities, the primary diagnosis is not 6B61.

Mild cognitive disorder or dementia: Characterized by broader, progressive cognitive deficits without temporal relationship to trauma. Neuropsychological evaluation shows a diffuse pattern of impairment, not selective for traumatic autobiographical memories.

Organic amnesia: Results from brain injury, neurological disease, or substance effects. Medical investigation identifies organic substrate. The pattern of memory loss is usually not selective for traumatic events.

Posttraumatic stress disorder: May include amnesia for aspects of the trauma, but the primary diagnosis is PTSD when symptoms of reexperiencing, avoidance, and hyperarousal predominate. Use 6B61 when amnesia is the dominant and disproportionate manifestation.

8. Differences with ICD-10

Equivalent ICD-10 code: F44.0 - Dissociative amnesia

Main changes in ICD-11:

The transition from ICD-10 to ICD-11 brought important refinements in the conceptualization and coding of dissociative amnesia. In ICD-10, dissociative amnesia was included in dissociative (conversion) disorders under code F44.0, with less emphasis on differentiation of subtypes.

ICD-11 introduces a clearer structure with explicit specifiers, particularly the distinction between dissociative amnesia with and without dissociative fugue (6B61.0 versus 6B61.Z). This differentiation allows better clinical characterization and facilitates research on specific subtypes.

The diagnostic criteria in ICD-11 are more explicit regarding the need to exclude organic causes, emphasizing that amnesia should not be due to substances, medications, diseases of the nervous system, or traumatic brain injury. This clarification reduces diagnostic ambiguity.

ICD-11 also more explicitly emphasizes the requirement for significant functional impairment, aligning with modern diagnostic approaches that value clinical impact beyond the mere presence of symptoms.

Practical impact of these changes:

The greater specificity of the criteria facilitates diagnostic consistency among different professionals and health services. The clearer hierarchical structure of ICD-11 aids in navigation between related codes and in differentiation of similar diagnoses.

For research purposes, more precise coding allows for more robust epidemiological studies and more valid international comparisons. Health information systems benefit from reduced ambiguity in coding.

Professionals should be attentive during the transition period, ensuring that electronic health record systems are updated and that teams receive adequate training on the new diagnostic categories and criteria.

9. Frequently Asked Questions

1. How is dissociative amnesia diagnosed?

The diagnosis is essentially clinical, based on detailed interview, mental status evaluation, and exclusion of organic causes. The clinician should document the nature and extent of amnesia, its temporal relationship to stressful events, and functional impact. Complementary neuropsychological evaluation helps characterize the memory profile. Medical examinations (laboratory, neuroimaging) are necessary to exclude organic causes. Structured instruments such as the Structured Clinical Interview for Dissociative Disorders may assist, but do not replace careful clinical evaluation.

2. Is treatment available in public health systems?

The availability of specialized treatment for dissociative amnesia varies significantly among different health systems and regions. Many public mental health services offer psychotherapy, which is the primary treatment for this disorder. Approaches such as trauma-focused cognitive-behavioral therapy, psychodynamic therapy, and specific techniques for dissociative disorders may be accessible through public services, although the availability of professionals specialized in dissociative disorders may be limited. Patients should seek information from mental health services in their region about available therapeutic options.

3. How long does treatment last?

The duration of treatment varies considerably depending on the severity of amnesia, the complexity of underlying trauma, the presence of comorbidities, and individual response to therapy. Some cases of localized amnesia related to a single traumatic event may resolve in weeks to months with appropriate intervention. More complex cases, especially those with generalized amnesia or related to chronic trauma, may require treatment for several months to years. Memory recovery is not always the primary goal; often the focus is on improving functioning and processing trauma in ways that do not depend on complete memory recovery.

4. Can this code be used in medical certificates?

Yes, code 6B61 can and should be used in medical documentation when appropriate, including certificates that justify absence from activities. Dissociative amnesia constitutes a legitimate medical condition that can cause significant functional impairment, justifying temporary absence from work or other activities. Documentation should be professional and focused on functional impact, without necessarily detailing specific traumatic content. Clinicians should be aware of confidentiality issues and discuss with the patient what information will be included in documents that may be seen by third parties.

5. Is dissociative amnesia permanent?

Not necessarily. The prognosis varies considerably. Some patients experience spontaneous memory recovery, particularly in cases of localized amnesia related to a single event. Others recover memories gradually during the therapeutic process. In some cases, especially generalized amnesia for entire life history, recovery may be partial or memories may not return completely. It is important to note that memory recovery is not always necessary for functional improvement; many patients learn to live satisfactorily despite memory gaps, focusing on building a new life narrative and processing the emotional impact of trauma.

6. Can dissociative amnesia occur in children?

Yes, children and adolescents can develop dissociative amnesia, often in response to abuse, neglect, or exposure to violence. Diagnosis in pediatric populations requires careful consideration of developmental factors, as young children have limited capacity to form and retrieve detailed autobiographical memories under normal circumstances. Assessment should include information from multiple sources (parents, teachers) and consider atypical presentations. Treatment generally involves age-appropriate approaches and may include family therapy when appropriate.

7. Is there specific medication for dissociative amnesia?

There is no specific medication that reverses dissociative amnesia. Treatment is primarily psychotherapeutic. However, medications may have an adjunctive role in managing comorbid symptoms such as depression, anxiety, or post-traumatic stress symptoms that frequently accompany dissociative amnesia. Antidepressants, particularly selective serotonin reuptake inhibitors, may be useful for these associated conditions. Benzodiazepines should be used cautiously due to the potential for dependence and possible interference with memory processing during therapy. Any medication treatment should be part of a comprehensive therapeutic plan centered on psychotherapy.

8. How to differentiate dissociative amnesia from malingering?

This differentiation can be challenging but is clinically important. In genuine dissociative amnesia, the patient typically demonstrates real distress about the memory loss and its functional impact. The pattern of amnesia generally follows known clinical characteristics (e.g., amnesia for traumatic events with preservation of other memories). Neuropsychological evaluation may reveal patterns inconsistent with malingering. In malingering, there may be inconsistencies between reports at different times, patterns of "memory loss" that do not follow known neuropsychological principles, and evidence of clear external motivation (financial gain, avoiding legal responsibility). Detailed interviews, collateral information, and longitudinal evaluation are essential. It is important to approach suspected cases with sensitivity, as premature accusations may harm genuine patients.

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Conclusion:

Dissociative amnesia (ICD-11: 6B61) represents a significant dissociative disorder that requires careful evaluation, precise differentiation from other conditions, and appropriate coding. Clear understanding of diagnostic criteria, situations of application, exclusions, and differentiation of related codes is essential for quality clinical practice. Appropriate documentation not only facilitates individual patient care but also contributes to accurate epidemiological data and advancement of knowledge about this complex condition. Healthcare professionals should stay updated on ICD-11 guidelines and seek specialized training when necessary to appropriately manage patients with dissociative disorders.

External References

This article was prepared based on reliable scientific sources:

1. 🌍 WHO ICD-11 - Dissociative amnesia
2. 🔬 PubMed Research on Dissociative amnesia
3. 🌍 WHO Health Topics
4. 📋 NICE Mental Health Guidelines
5. 📊 Clinical Evidence: Dissociative amnesia
6. 📋 Ministry of Health - Brazil
7. 📊 Cochrane Systematic Reviews

References verified on 2026-02-03