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Delusions and hallucinations in dementia with Lewy bodies: worsening with memantine

B H Ridha1, K A Josephs, M N Rossor

  • 1Dementia Research Centre, National Hospital for Neurology and Neurosurgery, London, WC1N 3BG, UK. bridha@dementia.ion.ucl.ac.uk

Neurology
|August 10, 2005
PubMed

Insights

Memantine therapy can worsen delusions and hallucinations in patients with dementia with Lewy bodies (DLB). Discontinuing the drug led to symptom improvement, suggesting caution is needed when prescribing memantine for possible DLB.

Area of Science:

  • Neuroscience
  • Geriatric Medicine
  • Pharmacology

Background:

  • Dementia with Lewy bodies (DLB) is a common neurodegenerative disorder.
  • Memantine is a medication used to treat moderate to severe Alzheimer's disease dementia.
  • The use of memantine in DLB patients requires careful consideration due to potential adverse effects.

Observation:

  • Three patients diagnosed with probable dementia with Lewy bodies (DLB) were treated with memantine.
  • These patients exhibited an exacerbation of psychotic symptoms, including delusions and visual hallucinations, after initiating memantine therapy.

Findings:

  • Memantine treatment was associated with a significant worsening of delusions and visual hallucinations in patients with probable DLB.
  • Discontinuation of memantine resulted in a notable improvement and resolution of these neuropsychiatric symptoms.

Implications:

  • Prescribers should exercise caution when considering memantine for patients with suspected or probable DLB.
  • The findings suggest that memantine may precipitate or exacerbate psychotic symptoms in this patient population.
  • Further research is warranted to elucidate the specific mechanisms and prevalence of memantine-induced adverse effects in DLB.

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