Parkinson's Disease

Question 1

Classification of Parkinson’s

Answer 1

• idiopathic -> just get it
• latrogenic -> drug induced particularly in antipsychotics
• post-traumatic -> after brain injury

Question 2

In those with parkinsons’s disease, there is more

Answer 2

ACh and less dopamine

Question 3

Drugs that raise dopamine levels

Answer 3

• l-DOPA
• selegiline/deprenyl inhibits metabolism of dopamine by MAO-B
• entacapone inhibits COMT

Question 4

Drugs that stimulate post-synaptic dopamine receptors

Answer 4

• bromocryptine, pergolide, pramipexole

Question 5

Drug that stimulates release of dopamine

Answer 5

amantadine

Question 6

Drugs that reduce cholinergic activity
centrally acting muscarinic antagonists

Answer 6

benztropine
diphenhydramine (BENADRYL)

Question 7

addition of Carbidopa to l-DOPA can

Answer 7

reduce metabolism of DOPA to dopamine by about 75% and decreases severity of some peripheral side effects

Question 8

Therapeutic effects of l-DOPA

Answer 8

• takes 3-4 weeks before full effect
• less pronounced effects as disesase progresses

Question 9

Side effects of l-DOPA

Answer 9

• nausea and vomiting due to stimualtion of chemoreceptor trigger zone by dopamine

Question 10

Cardiovascular effects of l-DOPA

Answer 10

postural hypotension
tachycardia
arrhythmias

Question 11

Behavioral effects of l-DOPA

Answer 11

-psychotic rxns, hallucinations, nightmares, mood changes
- increased libido and release of inhibitions
antipsychotic clozapine effective for managing psychiatric side effects

Question 12

Choreiform movements (writhing movements)

Answer 12

after long term therapy or when used with carbidopa

Question 13

end of dose phenomenon

Answer 13

decline in blood levels of l-DOPA near the end of dosage interval

Question 14

on-off phenomenon

Answer 14

can occur at any time in dosage interval and appears to be related to the progression of disease
effects minimized by using sustained release preparation or by adding COMT inhibitor or dopamine agonist

Question 15

Contraindications of l-DOPA

Answer 15

• cardiac arrhythmias
• psychosis
• melanoma
• glaucoma
• active peptic ulcer disease

Question 16

Sinemet =

Answer 16

carbidopa + l-DOPA

Question 17

Bromocryptine

Answer 17

nonspecific DA receptor agonist
less effective than l-DOPA

Question 18

Bromocryptine side effects

Answer 18

• nausea vomiting
• postural hypotension
• mental disturbances
• choreiform movements

Question 19

Ropinirole, Pramipexole, and Rotigotine

Answer 19

newer non-ergot dopaminergic agonists that target D2 and D3 receptors
now being used as first line drugs
less severe side effects
Rotigotine is a new long-acting patch product

Question 20

Amantadine (activity, side effects)

Answer 20

antiviral agent
stimualtes release of dopamine
side effects:
mental disturbances, choreiform movements

Question 21

Selegiline

Answer 21

selectively inhibits MAO-B and prevents breakdown of dopamine in CNS

Question 22

Entacapone and tolcopone

Answer 22

inhibit metabolism of dopamine and l-DOPA by COMT
provide more sustained blood level of I-DOPA

Question 23

Anticholinergic drugs

Answer 23

effective in milk parkinsons
more effective agonist tremor than rigidity
side effects: dry mouth, constipation, dry hot skin, blurring of vision