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Flashcards in Parkinson's Disease Deck (39)
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1

Clinical signs of PD (TRAP pneumonic)

-Tremor at rest
-Rigidity
-Akinesia or bradykinesia
-Postural/gait instability

2

Neurotransmitters involved in PD

-Dopamine*** (deficiency)
-NE
-ACh
-Glutamate
-Seratonin

3

"1st Line PD drugs"

-Levodopa plus carbidopa +/- entacopone
-Dopamine agonists

4

"2nd Line PD drugs"

-Anticholinergics
-Selective MOA B inhibitors
-NMDA antagonists

5

Levodopa Products

-Carbidopa/Levodopa
-Carbidopa/Levodopa/Entacapone

6

Levodopa MOA

Travels to BBB where it gets decarboxylated to dopamine

7

Carbidopa MOA

-blocks conversion of levo to dopamine before BBB
-*Minimize N/V, orthostatic hypoTN ass with levo

8

Entacapone

-Prolong action of levo by inhibiting O-methylation

9

Anticholinergics

Trihexyphenidyl and Benztropine

10

Anticholinergics MOA

Dopamine depletion in PD = state of cholinergic sensitivity, cholinergic drugs excite and anticholinergic drugs improve parkinsonian symptoms

11

Clinical indications of anticholinergics

Early: mild tremor
Later: enhance the effects of levodopa, *may help with drooling but ADRs frequently limit widespread application*

12

Anticholinergics pearl

Both can be used to treat drug-induced EPS

13

NMDA Antagonists

Amantadine

14

NMDA MOA

Increase dopamine release, decrease dopamine reuptake, stimulate dopamine receptors; interferes with excessive glutamate neurotransmission

15

Clinical indications of NMDA Antagonists

Early: limited data
Later: *adjunct tx, usually in pts with levodopa-induced dyskinesia)
Less effective after 1 year of use

16

NMDA Antag Interactions

Amantadine + anticholinergics/ETOH --> additive adverse effects on mental function

17

NMDA Antag ADRs

Low-dose: well tolerated
High-dose: sedation/confusion, anticholinergic ADRs, *LIVEDO RETICULARIS*, *sudden withdrawal may cause exacerbation of parkinsonian symptoms or NMS*

18

Adenosine A2A Rec Antag

Istradefylline

19

Clinical indications of Adenosine A2A Rec Antag

Adjunct to carbidopa/levodopa in adults with PD who experience "off" episodes

20

Adenosine A2A Rec Antag pearls

Pts who smoke over 20 ciggies/day need higher dose
Do NOT use in pts with major psychotic disorder

21

Most common ADR of Adenosine A2A Rec Antag

Dyskinesia

22

Levodopa Pearls

-Most effective drug for sx tx (akinetic sx > tremor/rigidity >> postural instability)
-"on" time 5-6 hrs, 5-6 doses needed/day
-new pts- take with snack
-advanced pts: take on empty stomach

23

Carbidopa Pearls

No activity on its own

24

Entacapone Pearls

-No activity on its own
-When added, levo dose needs to be decreased
-May cause orange urine

25

Levo dosing/admin

-ER cap--> swallow whole or sprinkle on applesauce
-ER used once IR tolerated
-No response >1000 mg/day, probs not PD

26

Levodopa Product Pk

-Absorption issues: high protein, iron foods
-Block metabolism: MOAI (HTN crisis)

27

Levodopa Product Pd

-Block levo effects--> anti-HTN meds
-Old antipsychotics/old nausea meds--> dopamine receptor blockade

28

Levodopa Products ADRs

-N/V, anorexia
-**Orthostatics--> common w initiation and increasing dose; no alpha-antagonists (BPH meds, cavedilol)
-CNS--> vivid dreams, hallucinations, delusion, confusion (with chronic therapy or dose escalation)**

29

Levodopa "special" ADRs

-"On-off" fluctuations- >5 yr therapy
-Wearing off syndrome- end of dose effect <4hr following dose
-Neurotox?
-Inhalation levo- cough, URI, sputum discoloration

30

Dopamine Receptor Agonists (ergot derivates)

-Bromocriptine
-**Minimal use d/t ADRs