Parkinson Disease

Question 1

What drug is a dopamine prodrug and is used primarily in the treatment of Parkinson’s Disease?

Answer 1

Levodopa (most effective agents for PD).
Given with Carbidopa which prevents the peripheral metabolism of levadopa so that levodopa can make it to the point of crossing the blood-brain barrier.

Brand name: Sinement

Question 2

What is the primary treatment for Parkinson’s Disease in terms of MOA and/or pathophysiology?

Answer 2

Dopamine replacement

Question 3

Other than dopamine prodrug and dopamine agonists, what other drug classes are used in the treatment of Parkinson’s Disease?

Answer 3

Anticholinergic agents and MAOI

Question 4

In Parkinson’s Disease, what are other related health condition that psychiatry patients can experience and what is the preferred treatments for it?

(hint: 2 conditions)

Answer 4

Depression:
SSRI/SNRI and TCA Secondary Amines such are nortriptyline and desipramine

Psychosis:
(in the late stage of the disease, sometimes due to meds to treat PD)
Quetiapine is preferred
Clozapine can be used too

Question 5

True or False:

In Parkinson’s Disease, symptoms like tremors can start at one side of the body then progress to both sides?

Answer 5

True

Question 6

Pathophysiology of Parkinson’s disease

Answer 6

A neurological disorder which occurs when the neuron in the substantial nigra in the brain die or become impaired.
These cells release dopamine (which is responsible for movement and balance) and when about 80% of them die, the disease appears.

Question 7

What are the symptoms of Parkinson’s Disease?

Answer 7

Motor symptoms: TRAP

• Tremors at rest
• Rigidity in the arm/leg/trunk
• Akinesia/Bradykinesia (slow movement)
• Postural instability (falls)

Question 8

SubCu dopamine agonist contraindication and ADE in the treatment of Parkinson’s Disease

Answer 8

Contraindication:
Do not use with 5HT3 antagonist such as ondansetron due to severe hypotension and loss of consciousness

ADE:
Severe N/V
Hypotension

Question 9

What is the starting dose of Sinement IR?

Answer 9

25/100 mg PO TID

Titrate slowly

Question 10

Dopamine agonist ADE in Parkinson’s Disease

Answer 10

Somnolence (sudden daytime sleep attacks)
Orthostasis
Hallucinations
Dyskinesias

Question 11

Why are Non selective MAOI contraindicated with drugs which treat Parkinson’s Disease?

Answer 11

B/c nonselective MAOI would block dopaminergic drug metabolism which is how Parkinson’s Disease drugs work.

i.e. Drug - Drug interaction

Question 12

Sinement ADE

Answer 12

Nausea, Dizziness
Orthostasis
Dyskinesia
** Brown, black or dark urine, saliva, or sweat
** Positive Coombs test: d/c drug due to hemolysis risk
** Unusual sexual urges
** Priapism
Long-term use can cause flactuations and dyskinesia

Question 13

What scale is used to measure involuntary movements like tar dive dyskinesias?

Answer 13

Abnormal Involuntary Movement Scale (AIMS)

Question 14

What drug is used in Parkinson’s Disease which works by blocking dopamine reuptake into the presynaptic neurons and increase dopamine release form presynaptic fiber?

ADE?

Answer 14

Amantadine

Dizziness
Orthostatic hypotension

Can cause somnolence and psychosis

Question 15

Can Sinemet be crushed of chewed?

Answer 15

Nope

Question 16

What is the function of COMT inhibitor in the treatment of Parkinson’s Disease?

What is the one drug in this class?

Answer 16

It increases the duration of action of levodopa by inhibiting catechol-O-methyltransferase which metabolizes levodopa.

Entacapone (Comtan)

Question 17

What drug is a dopamine agonist used in the treatment of Parkinson’s Disease for initial treatment in younger patients and eventually in most patients?

Answer 17

Pramipexole (Mirapex)
Ropinirole (Requip)

Apomorphine (Apokyn) SC

Question 18

What are some odd symptoms which can occur with Parkinson’s Disease?

Answer 18

unusual urges for sex, gambling or uncontrollable buying sprees

Question 19

What class of drug are used in Parkinson’s Disease and work by blocking the breakdown of dopamine?

Agents?

Warning?

Answer 19

Selective MAOI

Selegiline (Zelapar)
Rasagiline (Azilect)

Serotonin syndrome
Hypertension

Question 20

At what age does Parkinson’s Disease develop?

Answer 20

Develops at the age of 65 but can also be diagnosis at < age 50.

Question 21

What drug is FDA approved in the treatment of hallucinations, delusions, psychosis in patients with Parkinson’s Disease?

Answer 21

Pimavanserin (Nuplazid)

Question 22

What are some Dopamine blocking drugs which can cause or worsen Parkinson’s Disease?

Answer 22

• Phenothiazines (like prochlorperazine) for psychosis, nausea, agitation
• Butyrophenones (like haloperidol, droperidol) for psychosis and behavioral
• 1st and 2nd gen antipsychotics
• Metoclopraminde

Question 23

What is the “off” periods in Parkinson’s Disease?

Answer 23

This is when symptoms of the disease worsen before the next dose of medication is due. These episodes present as muscle stiffness, slow movements and difficult starting movement.

Question 24

List the common drugs used in Parkinson’s Disease..

Answer 24

Dopamine replacement:
- Sinement (Carbidopa/Levodopa)

COMT-I:
- Entacapone (Comtan)

Dopamine agonist:

• Pramipexole (Mirapex)
• Ropinirole (Requip)
• Apomorphine (Apokyn)

Increase dopaimine via 2 folds in persynapsis:
- Amantadine

Anticholenergic:

• Benzotropine (Cogentin)
• Trihexyphenidyl

Selective MAO-I:

• Selegiline (Zelapar)
• Rasagiline (Azilect)

Question 25

What drug is a centrally-acting anticholinergic used in Parkinson's Disease? ADE?

Answer 25

Benzotropine (Cogentin) Trihexyphenidyl ``` Dry mouth Constipation Urinary retention Somnolence Confusion ```

Question 26

What are some drug-drug interactions with Sinement?

Answer 26

- Contraindicated with non-selective MAOI, must separate by 2 weeks - Iron and protein-rich food can decrease absorption - Do not use with dopamine blockers such as phenothiazines, metoclopramide