Parkinson

Question 1

Define Parkinson disease

Answer 1

a degenerative disorder of the CNS caused by death of neurons that
produce the brain neurotransmitter dopamine.

• progressive neurological disorder of muscle move

Question 2

Symptom

Answer 2

Tremors : The hands and head develop shakiness when at rest.
• Muscle rigidity : Patients often have difficulty bending over or moving
limbs.
• Bradykinesia : Patients may have difficulty chewing, swallowing, or
speaking.
• Postural instability : Patients may easily lose their balance

Question 3

Strategy of treatment

Answer 3

• Neostriatum is also rich in excitatory cholinergic neurons that oppose the
action of dopamine.
• Many of the symptoms of parkinsonism reflect an imbalance between the excitatory cholinergic neurons and the greatly diminished number of inhibitory dopaminergic neurons.
• Therapy is aimed at restoring dopamine in the basal ganglia and
antagonizing the excitatory effect of cholinergic neurons

Question 4

Staging disability of parkinson disease

Answer 4

1. Unilateral involvement only / minimal functional impairment
2. Bilateral involvement without impairment of balance
3. Evidence of postural imbalance
4. Severely disabled, can’t walk and stand unassisted
5. Restricted to bed or wheelchair unless aided

Question 5

Antiparkinsonism agents

Answer 5

• Antiparkinsonism agents restore the balance of dopamine
and acetylcholine in the corpus striatum of the brain.
• include dopaminergic agents and anticholinergics.

Question 6

Drugs used in parkinson disease

Answer 6

•aetiology
-degeneration of nigrostriatal neurons
•antimuscarinic drugs
-eg: procyclidine, orphenadrine
•MAOB inhibitors
-selegiline, rasagiline
•COMT inhibitor
-eg: entacapone, tolcapone
•dopaminergic drugs
-eg: levodopa, Dopamine agonists, ergot derivatives, bromocriptine, cabergoline, pergolide

Question 7

Dopaminergic agents

Answer 7

•Dopaminergic drugs are used to increase dopamine levels in the corpus striatum.
• Levodopa is a precursor of dopamine synthesis. Supplying it directly lead to increased synthesis of dopamine within the nerve terminals.
• Levodopa can cross the blood-brain barrier, but dopamine cannot.

Question 8

Anticholinergic agents

Answer 8

• produce fewer side effects. But they still cause autonomic effects such as dry mouth, tachycardia, and constipation that are troublesome.
• This agent acts by blocking the effect of acetylcholine, inhibit the over activity of this neurotransmitter in the corpus striatum of the brain.

Question 9

Antimuscarinics

Answer 9

• produce a modest improvement in the early stages of Parkinson’s disease, but the bradykinesia that is responsible for most of the functional disability responds least well.
• Furthermore, adverse effects are common and include dry mouth, urinary retention, and constipation.
• affect memory and concentration and precipitate an organic confusional state with visual hallucinations, especially in elderly / dementing
patients.
• The main use of these drugs is in the treatment of
drug‐induced parkinsonism