What are the causes of sudden amnesia (memory loss)?

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Differential Diagnosis for Sudden Memory Loss

  • Single most likely diagnosis
    • Transient Global Amnesia (TGA): A sudden, temporary episode of memory loss that is often triggered by stress, physical exertion, or medical procedures. It is characterized by an inability to form new memories, while memories of events prior to the onset of amnesia remain intact.
  • Other Likely diagnoses
    • Medication side effects: Certain medications, such as sedatives, antidepressants, and antihistamines, can cause memory loss as a side effect.
    • Sleep deprivation: Lack of sleep or disrupted sleep patterns can lead to impaired memory and cognitive function.
    • Depression: Depression can cause cognitive impairment, including memory loss, particularly in older adults.
    • Anxiety: Severe anxiety can impair memory and cognitive function, especially in situations where the individual is under stress.
  • Do Not Miss diagnoses
    • Stroke or Transient Ischemic Attack (TIA): A sudden loss of memory can be a symptom of a stroke or TIA, which requires immediate medical attention to prevent further brain damage.
    • Traumatic Brain Injury: A head injury can cause memory loss, and it is essential to rule out any underlying trauma.
    • Infections (e.g., meningitis, encephalitis): Certain infections can cause sudden memory loss and require prompt medical attention.
    • Hypoglycemia: Low blood sugar can cause confusion, disorientation, and memory loss, particularly in individuals with diabetes.
  • Rare diagnoses
    • Dementia with Lewy bodies: A progressive neurodegenerative disorder that can cause fluctuations in cognitive function, including memory loss.
    • Frontotemporal dementia: A rare form of dementia that can cause significant changes in personality, behavior, and memory.
    • Korsakoff syndrome: A rare brain disorder caused by a lack of thiamine (vitamin B1) that can lead to memory loss and confusion.
    • Epilepsy: Certain types of seizures can cause transient memory loss or confusion.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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