Antiparkinsonian- Dopamine Replacement UNIT 5 Catechol O- Methyltransferase (COMT) Inhibitor UNIT 5

Question 1

What is Parkinson’s Disease

Answer 1

Parkinson’s Disease
 Chronic neurologic disorder for which there is no cure. Symptoms are managed
with medication
 Imbalance of dopamine – not enough
 Imbalance of acetylcholine – too much
 Causes degeneration of neurons of the extrapyramidal motor tract
 Symptoms worsen as the disease progresses

Question 2

S/S OF PARKINSON’S DISEASE

Answer 2

Parkinson’s Disease and Pseudoparkinsonism
Signs and Symptoms
 Signs and Symptoms
 Pill rolling motion in hands
 Tremors of the head and neck
 Rigidity
 Postural changes
 Shuffling walk
 Bradykinesia (slow movement)
 Lack of facial expression
 No changes in cognitive level

Question 3

DRUG therapy for Parkinson’s

Answer 3

Parkinson’s Disease Treatments
 Anticholinergic drugs*
 Block cholinergic receptors – see anticholinergic presentation
 Dopaminergics*
 Drug converts to dopamine
 Dopamine agonists
 Stimulate dopamine receptors
 MAO-B inhibitors
 Inhibit MAO-B enzyme that interferes with dopamine
 COMT inhibitors*
 Inhibit COMT enzyme that inactivates dopamine
 *The drug classifications you are responsible for knowing

Question 4

Which of the following drug is used to convert dopamine in the brain to help slow the progression of Parkinson’s Disease

A. Carbidopa and Levodopa
B. Atenolol
C. Propranol
D. Zinc

Answer 4

A. Carbidopa and Levodopa

Action
 Levopdopa goes to brain cells to convert to dopamine
 Carbidopa blocks the conversion peripherally so levodopa can get to the brain
 Uses
 Treat the signs and symptoms of Parkinson’s disease.
 Does not cure Parkinson’s disease

Question 5

Side effects of Carbidopa Levodopa

Answer 5

Anorexia, nausea, vomiting, dysphagia, dyskinesia, erythema, fatigue, dizziness, headache, dry mouth, constipation, bi er taste, twitching, blurred vision, insomnia, excess dark sweating, urine discoloration (red, brown, or black)

GI distress, dry mouth
 Fatigue, insomnia, dizziness, headache, blurred vision
 Dark urine
 Orthostatic hypotension,

Question 6

Adverse Effect of Carbidopa Levodopa

Answer 6

Palpitations
 Hypotension
 Urinary retention
 Psychosis, severe depression

involuntary movements, angioedema, palpitations, orthostatic hypotension, urinary retention, priapism, psychosis, depression with suicidal ideation, hallucinations, sudden sleep onset, impulse control symptoms
Life threatening: Agranulocytosis, hemolytic anemia, leucopenia, thrombocytopenia, cardiac dysrhythmias; abrupt discontinuation may cause neuroleptic malignant syndrome

Question 7

Antiparkinson’s drugs – Dopaminergics –
Carbidopa and Levodopa CONTRAININDICATIONS

Answer 7

Antiparkinson’s drugs – Dopaminergics –
Carbidopa and Levodopa
 Contraindications
 Antipsychotics
 Drug and Food interactions
 Many!
 High protein foods decrease absorption

Question 8

Which of the following drugs is Catechol-O-Methyltransferase Inhibitors

A. Benztropine
B. Altropine
C. Tolcapone
D. Ibuprofen

Answer 8

Action
 Inhibits catechol O-methyltransferase (COMT)
 COMT inactivates dopamine so this drug inhibits COMT which results in increase dopamine
 Not given alone – always given with levodopa
 Prolongs the action of levodopa by stopping levodopa from ‘wearing off’

Question 9

Is Tolcapone always given with levodopa

A. yes
B. no

Answer 9

A. yes

 Not given alone – always given with levodopa

Question 10

Does Tolcapone increase the drug life of Levodopa in the brain

Answer 10

Hepatotoxic – contraindicated in patients with liver disease
 Levodopa dose is decreased once this drug is started
 Can intensify the adverse reactions of levodopa because they prolong the effect of
levodopa
 Similar to carbidopa/levodopa

Question 11

Is Tolcapone liver toxic

A. No
B. Yes

Answer 11

B. Yes

Question 12

A patient has recently been prescribed levodopa due to his recent diagnosis of Parkinson’s Disease. Which statement made by the patient requires further teaching?

A. I should eat a low protein diet
B.l shouldn’t take the medication with food
C. I should call 911 if my urine is red or dark
D. Benztropine is used to help decrease muscle rigidity and tremors

Answer 12

C. I should call 911 if my urine is red or dark

 Levodopa may cause harmless discoloration of urine and sweat to brown

Question 13

Patient Teaching for Levodopa

Answer 13

Antiparkinson’s drugs – Nursing care plan
 Teach
 Take on empty stomach
 Take at the same times each day
 Take with low protein foods if stomach upset occurs
 Do not abruptly discontinue drugs
 Levodopa may cause harmless discoloration of urine and sweat to brown

Question 14

EVALUATION OF ANTI-PARKINSINM DRUGs

Answer 14

Evaluation
 Improved symptom control
 Patient and family understanding of the medications
 Side effects/Adverse reactions minimized