Parkinson drugs

Question 1

what is Levodopa typically used for in Parkinson Disease

Answer 1

to control bradkinetic symptoms

Question 2

MOA of Levodopa

Answer 2

converted to dopamine by DOPA decarboxylase at the presynaptic neuron to stimulate D2 receptors

Question 3

Side effects of Levodopa (alone)

Answer 3

• GI: Anorexia, N/V
• CVS: Arrhythmias. tachycardia, postural hypotension
• Behavior: depression, anxiety, agitation, insomnia, confusion, hallucinations, nightmares, euphoria
• choreoathetosis of the face and distal extremities
• wearing off/ off and on phenomena
• mydriasis may precipitate glaucoma, gout, and taste abnormalities
• brown secretions
• peripheral neuropathies

Question 4

contraindications of Levodopa(alone)

Answer 4

Psych patients (may exacerbate psychosis)

Angle closure glaucoma (may exacerbate mydriasis)

Peptic ulcer disease

melanoma

Question 5

interactions of Levodopa

Answer 5

antacids decrease bioavailability

ACh drugs and antipsych drugs may decrease serum levels/ effects

combination with MAOIs can cause HTN crisis and hyperpyrexia

B6 increases metabolism

can be antagonized by phenothiazines when not used with carbidopa

Question 6

MOA of carbidopa

Answer 6

reduces peripheral conversion of Levodopa to dopamine and inhibits aromatic amino acid decarboxylase

Question 7

does Carbidopa cross the BBB

Answer 7

no

Question 8

AChR antagonists used in Parkinson Disease

Answer 8

Benztropine

Trihexyphenidyl

Question 9

When are AChR antagonists used for Parkinson Disease?

Answer 9

patients who are 65 or younger and have a disturbing tremor, but no gait disturbance or bradykinesia

Question 10

MOA of AChR antagonists

Answer 10

inhibits excitatory cholinergic neurons to decrease the concentration of ACh

Question 11

Side effects of Benztropine and Trihexyphenidyl

Answer 11

Agitation

confusion

Constipation

Delerium

Dry mouth

Memory loss

urinary retention

tachycardia

Question 12

Cautions and contraindications of using AChR antagonists

Answer 12

Caution: patients with closed-angle glaucoma

Contraindications: memory impaired, confused, hallucinating patients

Question 13

Interactions with AChR antagonists

Answer 13

has additive anticholinergic effects with antihistamines and phenothiazines

Question 14

What are the MAO-B Inhibitors and what are they used for

Answer 14

Selegiline, Rasagiline, Safinamide

Reduces mild on-off/ wearing off phenomena

for patients with declining or fluctuating response to Levodopa

Decreases free radicals and inhibits disease progression

Question 15

MOA of MAOI-B Inhibitors

Answer 15

selectively and irreversibly inhibits MAO-B to increase dopamine in basal ganglia

Question 16

MAO-B Inhibitor side effects

Answer 16

confusion

dyskinesias

hallucinations

hypotension

insomnia

nausea

Question 17

Interactions of MAO-B Inhibitors

Answer 17

If taken with Meperidine: causes serotonin syndrome

With foods rich in tyrosine: hypertensive crisis

Rasagiline may enhance adverse effects of Levodopa

Question 18

Most potent MAO-B inhibitor to prevent MPTP induced Parkinsonism

Answer 18

Rasagiline

Question 19

The difference in the COMT inhibitors and what are they used for

Answer 19

Entacapone: peripheral COMT inhibitor

Tolcapone: Central COMT inhibitor

patients taking Levodopa who have fluctuations

Question 20

MOA of COMT inhibitors

Answer 20

inhibits COMT to decrease the metabolism of dopamine

Question 21

Side effects of COMT Inhibitors

Answer 21

Nausea

diarrhea

orange secretions

Question 22

Contraindications of Tolcapone

Answer 22

Liver failure

only use if patient is unresponsive to other therapies

Question 23

Interactions of COMT Inhibitors

Answer 23

decreases Levodopa clearance to increase the overall concentration in circulation

Question 24

What is Amantadine used for and what is its MOA

Answer 24

Influenza A and early/ late-stage Parkinsonism

NMDA antagonist that potentiates dopaminergic function by influencing the synthesis, release and reuptake of dopamine

Question 25

Side effects of Amantadine

Answer 25

**dry mouth** hypotension **Livedo reticularis** nausea **restlessness** sedation vivid dreams

Question 26

What drugs can potentiate the effects of Amantadine

Answer 26

Benztropine Trihexyphenidyl

Question 27

What kind of disorders are dopamine receptor agonists most commonly associated with

Answer 27

impulse control disorders

Question 28

which dopamine receptor agonists prefer D2 receptors and which prefer D3

Answer 28

D2: Bromocriptine and Ropinrole D3: Pramipexole Apomorphine is a general dopamine agonist

Question 29

Side effects of Bromocriptine

Answer 29

confusion **decreased prolactin** dry mouth dyskinesias **hallucinations** nausea **orthostatic hypotension** sedation **vivid dreams** **suppression of lactation**

Question 30

Interactions of Bromocriptine

Answer 30

cardiac valve fibrosis pulmonary fibrosis

Question 31

When is Pramipexole used

Answer 31

advanced parkinson disease

Question 32

Side effects of Pramipexole and Ropinrole

Answer 32

dizziness hallucinations insomnia

Question 33

interactions of Pramipexole

Answer 33

Cimetidine increases levels

Question 34

Which dopamine receptor agonist is contraindicated with breastfeeding

Answer 34

Ropinrole

Question 35

What is apomorphine used for

Answer 35

rescue during off periods of akinesia in patients on dopaminergic therapy

Question 36

Side effects of Apomorphine

Answer 36

N/V Dyskinesia Drowsiness Hypotension Chest pain

Question 37

component of synthetic drugs that **cause** parkinsonism

Answer 37

MPTP

Question 38

MOA of MPTP

Answer 38

inhibits mitochondrial oxidation, causing irreversible destruction of nigrostriatal dopaminergic neurons