Prolonged QT interval, syncope, and delirium with galantamine
Alexander A Fisher1, Michael W Davis
1Australian National University Medical School, Australia. alex.fisher@act.gov.au
The Annals of Pharmacotherapy
|January 10, 2008
Summary
Acetylcholinesterase inhibitors (AChIs) like galantamine can cause serious side effects including QT interval prolongation, syncope, and delirium. Careful patient monitoring is essential when prescribing these dementia medications.
Area of Science:
- Geriatric Medicine
- Clinical Pharmacology
- Neuroscience
Background:
- Acetylcholinesterase inhibitors (AChIs) are commonly prescribed for dementia.
- Galantamine is an AChI used to treat mild to moderate Alzheimer's disease.
Observation:
- An 85-year-old man experienced syncope, bradycardia, and hypotension while on galantamine.
- Discontinuation of galantamine led to cognitive and functional decline, prompting its reintroduction.
- Upon re-initiation, the patient developed syncope, delirium, hypotension, and QT interval prolongation with cardiac arrhythmias.
Findings:
- The patient's delirium resolved, and QT interval normalized after discontinuing galantamine.
- Analysis of Australian Adverse Drug Reaction Advisory Committee (ADRAC) reports revealed associations between galantamine, donepezil, and rivastigmine with delirium, syncope, bradycardia, hypotension, and arrhythmias.
- Galantamine was identified as the probable cause of the patient's adverse events.
Implications:
- AChIs, including galantamine, can precipitate serious adverse events such as QT prolongation, syncope, and delirium.
- Vigilance and risk factor assessment are crucial during galantamine and other AChI administration.
- Healthcare providers should carefully weigh the benefits and risks of AChIs in elderly patients.
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