Ch 21: Drugs for Parkinson's Disease

Question 1

What are the first-line drugs for Parkinson’s Disease?

Answer 1

Dopamine agonists

p. 183

Question 2

What are the two groups of dopamine agonists?

Answer 2

derivatives of ergot (an alkaloid found in plants), nonergot derivatives

(p. 183)

Question 3

What are the 4 listed drugs used to treat PD included in the nonergot derivatives group?

Answer 3

pramipexole, ropinirole, rotigotin, apomorphine

p. 183

Question 4

What are the the listed drugs used to treat PD in the ergot derivatives group?

Answer 4

bromocriptine and cabergoline

p. 185

Question 5

What two COMT inhibitors are available to treat PD?

Answer 5

entacapone and tolcapone

p. 185

Question 6

How do COMT inhibitors work?

Answer 6

They are given as an adjunct to levodopa. The work by inhibiting metabolism of levodopa in the periphery.

(p. 185)

Question 7

Tolcapone has been known to cause deaths as a result of _____ _______.

Answer 7

liver failure

p. 185

Question 8

What is levodopa’s mechanism of action?

Answer 8

it increases dopamine synthesis in the striatum.

p. 179

Question 9

What two drugs for PD are known as MAO-B inhibitors?

Answer 9

selegiline and rasagiline

p. 186

Question 10

What are the cardinal symptoms of Parkinson’s Disease?

Answer 10

Motor symptoms include tremor, rigidity, postural instability, and slowed movement
Non-motor symptoms include depression, psychosis, dementia, and sleep disturbances

(p. 176)

Question 11

The underlying cause of motor symptoms in PD is…

Answer 11

…loss of dopaminergic neurons in the substantia nigra.

p. 176

Question 12

Dopamine is an ___________ neurotransmitter; acetylcholine is an __________ neurotransmitter.

Answer 12

inhibitory; excitatory

p. 176

Question 13

What pharmacologic category is amantadine?

Answer 13

anti-parkinson agent, dopamine agonist, and antiviral agent

[From Lexicomp]

Question 14

Amantadine (Symmetrel) was developed as an _________ agent, and was later found to be effective in __________ ______.

Answer 14

antiviral
Parkinson’s disease

p. 187

Question 15

Possible mechanisms include inhibition of dopamine uptake, stimulation of dopamine release, blockade of cholinergic receptors, and blockade of glutamate receptors. Responses develop rapidly – often within 2 - 3 days– but are much less profound than with levodopa or the dopamine agonists. Furthermore, responses may begin to diminish within 3 - 6 months. Accordingly, amantadine is not considered a first-line agent. However, the drug may be helpful for managing _________ caused by levodopa.

Answer 15

dyskinesias

p. 187

Question 16

Amantadine can cause adverse CNS effects (confusion, lightheadedness, anxiety) and peripheral effects that are thought to result from muscarinic blockade (blurred vision, urinary retention, dry mouth, constipation). All of these are generally mild when amantadine is used alone. However, if amantadine is combined with an _____________ agent, both the CNS and peripheral responses will be intensified.

Answer 16

anticholinergic

p. 187

Question 17

Patient taking amantadine for 1 month or longer often develop ______ ___________, a condition characterized by mottled discoloration of the skin. It is benign and gradually subsides following withdrawal of the drug.

Answer 17

livedo reticularis

p. 187

Question 18

Amantadine is eliminated primarily by the _______. It often loses its effectiveness after several months.

Answer 18

kidneys

p. 187

Question 19

In a study published in NEJM in March 2012, amantadine accelerated the pace of __________ ________ during active treatment in patients with post-traumatic disorders of consciousness. However, the rate of improvement in the experimental group then slowed, and the overall improvement in DRS (Disability Rating Scale) scores between baseline and week 6 (2 weeks after treatment was discontinued) was similar in the two groups.

Answer 19

functional recovery

[NEJM, Placebo-Controlled Trial of Amantadine for Severe Traumatic Brain Injury, March 2012]