Parkinson's

Question 1

Most effective tx for Parkinson’s?

Answer 1

Levodopa

Question 2

What do you give with Levodopa? Why?

Answer 2

Carbidopa.. Cuz levodopa is metabolized by L-AAD. Carbidopa inhibits L-AAD in the periphery but not in CNS –> need less levodopa dose & less AE’s

Question 3

AE’s of levodopa monotherapy?

Answer 3

Arrhythmias, orthostatic hypoTN… and GI upset

Question 4

Levodopa/Carbidopa AE’s?

Answer 4

Behavioral (give antipsychotics), hyperkinetic dyskinesias, may increase free radicals –> worsens Parkinsons

Question 5

Describe the “On-Off” phenomenon

Answer 5

Levodopa works great sometimes and sometimes it sucks.. There is no rhyme or reason to this (it is not dose dependent & does not come from increased tolerance - according to UWorld)

Question 6

Contraindications in levodopa?

Answer 6

Psychos, glaucoma, CV disease, PUD, melanoma. Also drug interaction w/ Vit B6

Question 7

What Parkinson’s dz drugs are dopamine agonists?

Answer 7

1. Apomorphine (NS)
2. Bromocriptime (D2/some D1)
3. Pramipexole (D2, free radical scavenger)
4. Ropinirole (D2, CYP1A2)
   * All Bros Prefer Rowdiness

Question 8

Preferred initial therapy in Parkinson’s?

Answer 8

Dopamine agonists

Question 9

What drug increases dopamine release?

Answer 9

Amantadine: an antiviral that treats the flu

**No effect on metabolism!!!

Question 10

Contraindications with Amantadine?

Answer 10

Seizures, CHF

Question 11

What drugs are dopamine metabolism inhibitors? (4 total drugs; 2 inhibiting each enzyme)

Answer 11

• MAO-B Inhs: Selegiline & Rasagiline

- COMT Inhs: Entacapone & Tolcapone

Question 12

Which dopamine metabolism inhs are neuroprotective and not that effective when used alone?

Answer 12

The MAO-B’s: Selegiline & Rasagiline

Question 13

What are the MAO-B’s (Selegiline & Rasagiline) metabolized to?

Answer 13

Amphetamine/methamphetamine

Question 14

What drugs do the MAO-B’s (Selegiline & Rasagiline) interact with?

Answer 14

Meperidine, TCAs, SSRIs

Question 15

What do COMT inhs do to levodopa?

Answer 15

Prolong its action & increase its bioavailability

*They also help reduce “ON-OFF”

Question 16

Are the COMT’s (Entacapone & Tolcapone) protein bound?

Answer 16

Yes

Question 17

Which COMT acts only peripherally?

Answer 17

Entacapone. Significant cuz no AE’s

Question 18

Tolcapone acts peripherally and centrally thus it has AE’s. What are they?

Answer 18

Hepatic failure!!!

Question 19

What Parkinson’s drugs are anticholinergic?

Answer 19

Block That Doo-doo:

Benztropine, Diphenhydramine, Trihexyphenidyl

Question 20

CNS AE’s of the anticholinergics

Answer 20

sedation, confusion, hallucination, mood change

Question 21

PNS AE’s of anticholinergics?

Answer 21

Opposite SLUDGEBBB

Question 22

Contraindications of anticholinergics?

Answer 22

BOGAT*

BPH, OBD (organic brain disease), glaucoma, anti-histamines (1st generation), TCAs

Question 23

What drug for Parkinson’s is a future drug that blocks L-type Ca channels?

Answer 23

Israpidine