442-Fin-Alzheimers

  1. Physostigmine
    • cholinesterase inhibitor, crosses BBB
    • based on "cholinergic hypothesis" where cholinergic deficits correlate with cognitive impairment and disease severity.
    • potent allosteric potentiating ligand of nicotinic receptors (same as galantamine); increases Nic channel opening induced by ACh, binds close to ACh-binding site on alpha subunit.
    • modest improvement in 3 weeks, side effects resolve in 1-3 weeks, effective for up to 2 years.
    • SE: insomnia, abnormal dreams, bradycardia, bronchoconstriction, increased secretion, DNVA, salivation, urinary urgency and incontinence, muscle cramps, profuse sweating.
    • Avoid antichol drugs: scopolamine, antihistamines, cough/cold, TCAs...
  2. Donepezil
    • selective acetylcholinesterase inhibitor, crosses BBB
    • based on "cholinergic hypothesis" where cholinergic deficits correlate with cognitive impairment and disease severity.
    • modest improvement in 3 weeks, side effects resolve in 1-3 weeks, effective for up to 2 years.
    • SE: insomnia, abnormal dreams, bradycardia, bronchoconstriction, increased secretion, DNVA, salivation, urinary urgency and incontinence, muscle cramps, profuse sweating.
    • Avoid antichol drugs: scopolamine, antihistamines, cough/cold, TCAs...
  3. Rivastigmine
    • acetyl & butyryl -cholinesterase inhibitor (non-competitive), crosses BBB
    • based on "cholinergic hypothesis" where cholinergic deficits correlate with cognitive impairment and disease severity.
    • modest improvement in 3 weeks, side effects resolve in 1-3 weeks, effective for up to 2 years.
    • SE: insomnia, abnormal dreams, bradycardia, bronchoconstriction, increased secretion, DNVA, salivation, urinary urgency and incontinence, muscle cramps, profuse sweating.
    • Avoid antichol drugs: scopolamine, antihistamines, cough/cold, TCAs...
  4. Tacrine
    • acetylcholinesterase inhibitor, crosses BBB
    • based on "cholinergic hypothesis" where cholinergic deficits correlate with cognitive impairment and disease severity.
    • NOT USED ANYMORE: liver toxicity...required liver function monitoring
  5. Galantamine
    • acetyl (weak) & butyryl -cholinesterase inhibitor (competitive), Nicotinic receptor modulation
    • based on "cholinergic hypothesis" where cholinergic deficits correlate with cognitive impairment and disease severity.
    • potent allosteric potentiating ligand of nicotinic receptors (same as physostigmine); increases Nic channel opening induced by ACh, binds close to ACh-binding site on alpha subunit.
    • modest improvement in 3 weeks, side effects resolve in 1-3 weeks, effective for up to 2 years.
    • SE: insomnia, abnormal dreams, bradycardia, bronchoconstriction, increased secretion, DNVA, salivation, urinary urgency and incontinence, muscle cramps, profuse sweating.
    • Avoid antichol drugs: scopolamine, antihistamines, cough/cold, TCAs...
  6. Memantine
    • N-Methyl-D-Aspartate Receptor Antagonist
    • treats mod-severe AD (chol, 5-HT, NA, HA inhibitory neurotransmission decreased, so more NMDA activation)
    • block NMDA to prevent calcium entry excitotoxicity, and down-regulation of NMDA receptors...restore balance.
    • also blocks alpha7, 9, 10 nicotonic subunits with ACh receptors, regulates release of glutamate from hippocampus and cortical neurons, non-competitive blockade
    • also non-competitively blocks 5-HT3 receptors which are ligand-gated ionoropic receptors for cations
  7. Anti-B-amyloid Antibodies
    intended to destroy insoluble, neurooxic beta-amyloid plaques that leads to inflammatory damage, dysfunction, and death of neurons...but trial withdrawn because 7% of subjects developed aseptic meningoencephalitis.
  8. Cevimeline
    • cholinergic agonist, muscarinic selective
    • 40x greater affinity for M1/M3 than M2
    • decreases extracellular accumulations of beta-amyloid peptide
    • may lead to decrease plaque formation
    • SE: less bradycardia (M2) than phenserine
  9. Phenserine
    • cholinergic agonist
    • phenylcarbamate of physosigmine
    • 1. potent AChesterase inhibitor
    • 2. normal fxning of Chol system regulates process of beta-amyloid precursor protein (APP)
    • therefore, beta-amyloid formation inhibited (same for all AChEs)
  10. Clioquinol, Alzhemed
    • ABeta amyloid aggregation inhibitor
    • could prevent formation of plaques
  11. Ginkgo Biloba
    • flavonoids + terpene-lactones + organic/coumaric acid suggested to increase cerebral bf in vitro
    • thereby inhibits aggregation of amyloid-beta, but only at high concentrations
    • flavonoids are antioxidants...not proven better than placebo
  12. Vitamin E (alpha-tocopherol)
    • antioxidant - decrease inflamm around plaques
    • 1000mg/day slow progression of disease?
  13. Selegiline
    • MAO-B inhibitor
    • inhibits breakdown of DA & 5-HT
    • may improve sx of AD but lacks global effect on disease
    • should not be given with many drugs
    • value uncertain
  14. NSAIDS?
    People who take NSAIDs regularly have lower incidence of Alzheimer's disease...but no benefit of treatment with an NSAID to persons with AD already
  15. Estrogen
    • post-men women on HRT have lower incidence of AD?
    • but combo of E + P increase chance of stroke (impaired cholesterol)
Author
jgiantess
ID
146709
Card Set
442-Fin-Alzheimers
Description
pharmacology
Updated