Neurology Flashcards
(12 cards)
Secondary parkinsonism is brain dysfunction that is characterized by basal ganglia dopaminergic blockade. It is similar to Parkinson disease, but it is caused by something other than Parkinson disease. Which of the following is the most common cause of secondary parkinsonism?
A.Severe depression
B.Early dementia
C.Use of antipsychotics
D.Cerebrovascular disease
Answer: C: Use of drugs that decrease dopaminergic actvity, including antipsychotics (eg, phenothiazine, thioxanthene, butyrophenone), antiemetics (eg, metoclopramide, prochlorperazine), and drugs that deplete dopamine (eg, tetrabenazine, reserpine) can cause secondary parkinsonism. A: Severe depression, especially in the elderly, can cause decreased spontaneous movements but does not cause parkinsonism. B: Parkinsonism is often preceded by dementia. D: Cerebrovascular disease can cause parkinsonism but is not the most common cause.
Levodopa is the most effective treatment. However, response to levodopa can wear off, causing fluctuations in motor symptoms and dyskinesias. Which is the best option when trying to minimize peak-dose dyskinesias?
A.Pramipexole
B.Ropinirole
C.Rotigotine
D.Amantadine
Answer: D: Amantadine is the best option when trying to minimize peak-dose dyskinesias. To reduce the time levodopa is taken and thus minimize fluctuations in motor symptoms and dyskinesias, clinicians can consider treating younger patients who have mild disability with MAO-B inhibitors (selegiline, rasagiline), dopamine agonists (eg, pramipexole [A], ropinirole [B], rotigotine [C]), or amantadine.
Anticholinergic drugs can be used as monotherapy in early Parkinson disease and later to supplement levodopa. They are most effective for which of the following symptoms?
A.Postural instability
B.Tremor
C.Rigidity
D.Bradykinesia
Answer: B: Tremor. Anticholinergic drugs are usually used only in young patients with tremor-predominant Parkinson disease or with some dystonic components. Rarely, they are used as adjunctive treatment in elderly patients without cognitive impairment or psychiatric disorders.
Levodopa action
What is it combined with
Side effects
Levodopa is absorbed by the nerve cells in your brain and turned into the chemical dopamine, which is used to transmit messages between the parts of the brain and nerves that control movement.
Increasing the levels of dopamine using levodopa usually improves movement problems.
It’s usually taken as a tablet or liquid, and is often combined with other medication, such as benserazide or carbidopa.
These medications stop the levodopa being broken down in the bloodstream before it has a chance to get to the brain.
They also reduce the side effects of levodopa, which include:
feeling and being sick
tiredness
dizziness
Long-term use of levodopa is also linked to problems such as uncontrollable, jerky muscle movements (dyskinesias) and “on-off” effects, where the person rapidly switches between being able to move (on) and being immobile (off).
Dopamine agonists
Dopamine agonists act as a substitute for dopamine in the brain and have a similar but milder effect compared with levodopa. They can often be given less frequently than levodopa.
They’re often taken as a tablet, but are also available as a skin patch (rotigotine).
Sometimes dopamine agonists are taken at the same time as levodopa, as this allows lower doses of levodopa to be used.
Possible side effects of dopamine agonists include:
feeling and being sick
tiredness and sleepiness
dizziness
Dopamine agonists can also cause hallucinations and increased confusion, so they need to be used with caution, particularly in elderly patients, who are more susceptible.
Monoamine oxidase-B inhibitors
Monoamine oxidase-B (MAO-B) inhibitors, including selegiline and rasagiline, are another alternative to levodopa for treating early Parkinson’s disease.
They block the effects of an enzyme or brain substance that breaks down dopamine (monoamine oxidase-B), increasing dopamine levels.
Both selegiline and rasagiline can improve the symptoms of Parkinson’s disease, although their effects are small compared with levodopa. They can be used alongside levodopa or dopamine agonists.
MAO-B inhibitors are generally very well tolerated, but can occasionally cause side effects, including:
feeling sick
headaches
abdominal pain
high or low blood pressure
The brain chemical whose diminishing is responsible for Parkinson’s disease is called:
epinephrine
dopamine
cortisol
adrenaline
Which of the following is a commonly overlooked initial non-motor symptom of Parkinson’s Disease?
a. Anosmia
b. Bradykinesia
c. Akinesia
d. Cogwheel rigidity
Diagnosis of Parkinson’s Disease is often delayed due to the fact that (CHOOSE ALL THAT APPLY):
a. It manifests later in life. Thus, early symptoms can be mistakenly attributed to normal ageing;
b. It manifests in early adulthood. Thus, early symptoms can be mistaken attributed to Huntington’s Chorea;
c. Its symptoms manifest gradually;
d. Its symptoms are characterised by frequent remissions and exacerbations;
e. It manifests primarily in African American women
The four cardinal symptoms of Parkinson’s Disease include:
a. Ageusia, bradykinesia, dementia and rigidity;
b. Tremor, bradykinesia, rigidity and postural instability;
c. Tremor, bradykinesia, seborrhea, and constipation;
d. Temor, bradykinesia, rigidity, and depression
The hallmark of Parkinson’s Disease pathophysiology is degradation of acetylcholine pathways in the nigro-striatal pathway of the midbrain.
(T/F)
Levodopa is a commonly used drug in the pharmacotherapy of Parkinson’s Disease. This drug’s mechanism of action of is be
a. A dopamine precursor that crosses the blood brain barrier and promotes synthesis of dopamine;
b. An anticholinergic drug that blocks muscarinic receptors in the midbrain;
c. Inhibition of dopamine breakdown;
d. Stimulation of dopaminergic receptors
