Pharmaco

  1. Neurotransmitters->
    20, others likely
  2. Parkinson’s
    Disease
    • 1 million Americans
    • •Neurodegenerative disorder

    • –Loss
    • of dopaminergic neurons in Basal Ganglion

    • –Decreased
    • dopamine

    • –Movement
    • requires balance between dopamine and ACh

    • •Rigidity,
    • tremor, instability, bradykinesia…akinesia

    •Therapeutic goal

    • –Improve
    • activities of daily living (ADL)

    • –Drug
    • selection and dosages are determined by ADL performance
  3. Why not just give dopamine?
    •Catecholamine

    –Must be given IV

    –Very short half-life



    –Can’t cross blood brain barrier
  4. Why not Levodopa/Dopar
    –Only 2% gets into brain

    •Need active transport

    –Metabolized to dopamine in the brain

    –Initially highly effective, then diminish over time

    –Wearing off-near dose time-(CR)

    –On/off-at any time maybe r/t protein
  5. Levodopa/Dopar (Adverse reactions and contraindication)
    •Adverse reactions

    •N/V, dyskinesias, dysrhythmias, hypotension

    •20% develop psychosis-clozapine is best choice

    •Contraindicated


        •malignant melanoma-can activate                  neoplasm

        •MAO inhibitors-hypertensive crisis
  6. Drug Holiday
    Taking up to 10 days off treatment can increase drug effectiveness.

    But it’s no picnic.
  7. Sinemet =
    Levodopa  +  Carbidopa
  8. •Carbidopa
    • –Blocksthe metabolizing of levodopa to dopamine in the gut 
    • –Increaseslevodopa in the brain
    • –Decreasesdopamine metabolism in periphery, so decreases cardiovascular effects
    • –Abnormalmovements and psychoses may occur sooner
  9. Dopamine Agonists
    •Increase activation of dopamine receptors

    •Less effective than dopamine

    –Best for mild symptoms

    –Not affected by proteins

    •Adverse effects: hallucinations, sedation, postural hypotension
  10. Dopamine Agonists
    • Promote activation of dopamine receptors
    •                                     •Selegiline/Carbex


    •Prevention of dopamine degradation

    • •Promotion of dopamine release, inhibits  reuptake              
    •              •Amantadine/Symmetrel–Anti-viral

    • •Direct activation of dopamine receptors
    •                                     •Ropinorole/Requip
  11. Anticholinergic agents? Examples
    Prevent activation of cholinergic receptors

    •Benztropine (Cogentin)



    •Blockade of cholinergic receptors

    •Decrease tremors and rigidity, not bradykinesias

    •Side effects:
  12. Hippocampus-
    • limbic system
    • memory, emotion, motivation  
    • spatial navigation
  13. Alzheimer’s Disease
    5.1 million Americans
    5.1 million Americans

    •Degeneration of cholinergic neurons

    –neuritic plaques, neurofibrillary tangles

    •Progressive memory loss

    •Neuropsychiatric symptoms

    •Neuromotor decline

    •Prognosis-4-8 years

    •10,000 die annually
  14. Cholinesterase Inhibitors
    –Mild to moderate symptoms

    –Prevent breakdown of Ach

    •Improve availability

    •Only 20-30% of patients respond



    –Donepezil (Aricept)-less side effects

    –Cholinergic side effects 

    •??
  15.  NMDA receptor antagonist
    memantin/namenda

    –N-methly-D-aspartate

    •For moderate to severe

    •Better tolerated than C I

    •Decreases and can reverse symptoms

    •Modulates action of glutamate

    Blocks extracellular influx of calcium in memory cells
  16. Alzheimer’s Disease Prevention
         -2010
    Possible benefit:

    •Mediterranean Diet

    •Folic Acid

    •Statins



    Minimal protection

    •Physical Activity

    •Cognitive training

    • No
    • benefit:

    • •Gingko
    • Biloba

    •Vitamins

    •Omega-3

    • •Beta
    • carotene

    •Estrogens

    •NSAIDS

    •ASA

    • •C
    • I

    •Antihypertensive

    •Homocysteine
Author
kodak168
ID
235514
Card Set
Pharmaco
Description
Nursing pharmacology
Updated