Parkinsons Disease

Question 1

Role of Parkinsons Meds

Answer 1

Designed to normalize dopamine activity in the BG

Question 2

What is the primary drug used to treat PD?

Answer 2

Levodopa- almost always improves the symptoms associated with parkinsonim (especially bradykinesia and rigidity)

Question 3

Levodopa mechanism of action

Answer 3

Levodopa is taken orally, absorbed through the GI tract and converted into dopamine by the enzyme dopa decarboxylase. Any thing converted into dopamine outside of the brain will be useless- only small amounts actually make it to the brain before being converted

Question 4

Why would taking dopamine orally or parenterally not be effective for treating PD?

Answer 4

It cannot cross the BBB and thus would never reach the brain

Question 5

Why would patients need to take such large quantities of levodopa?

Answer 5

Since so much of it is converted to dopamine in the periphery and is rendered useless

Question 6

Why is Carbidopa important?

Answer 6

Carbidopa inhibits the enzyme that converts levodopa into dopamine within the periphery which allows for more levodopa to reach the brain before being converted

Question 7

What is a Sinemet?

Answer 7

A manufactured pill containing both levodopa and carbidopa- these 2 drugs are almost always given together in order to allow for a smaller dosage of levodopa

Question 8

Side effects of Levodopa

Answer 8

-GI problems
-cardiac problems
-orthostatic hypotension
-dyskinesias
-behavioral changes (depression, anxiety, confusion, psychosis)

Question 9

When does Levodopa start to become less effective?

Answer 9

After prolonged use for a prolonged period of time- about 3-4 years

Question 10

What is the End of Dose Akinesia?

Answer 10

When the drug’s effectiveness wears off prior to the next dose
-can be resolved by adjusting the timing and quantity of doses

Question 11

What is the On-Off Phenomenon?

Answer 11

When the effectiveness of levodopa suddenly and spontaneously decreases which results in worse parkinsonian symptoms due to a drop in dopamine levels- known as the “off” phase
-can occur repeatedly throughout the day

Question 12

What does Freezing mean?

Answer 12

When a patient stops talking and appears to be frozen in an upright position- reason unknown

Question 13

What is a drug holiday and what is the overall goal?

Answer 13

Patient is gradually removed from all parkinsons meds for 3 days-3 weeks while being closely supervised when their drugs are no longer effective or their side effects become too severe

Goal: to let the body recover from any drug toxicity or tolerance due to prolonged usage

Question 14

Effectiveness of a Drug Holiday and Risks associated

Answer 14

50-70% of people benefit from them, however there are risk associated such as- DVT, PE, pneumonia, and other impairments because of immobility

Question 15

Which drugs are used for Parkinsons Disease?

Answer 15

-Levodopa
-Carbidopa
-Dopamine agonists
-Anticholinergic drugs
-Amantadine
-MAO-B Inhibitors
-Catechol-O-Methyltansferase Inhibitors

Question 16

When are dopamine agonists typically used?

Answer 16

Typically used with levodopa when it starts to become less effective or the patient has developed end-of-dose akinesia or On-Off Syndrome

Question 17

Which drugs alleviate acetylcholine to help with PD tremors and rigidity?

Answer 17

Anticholinergic Drugs- most effective when used with levodopa
-causes anticholinergic side effects

Question 18

What is the purpose of Amantadine?

Answer 18

Taken with Levodopa to help reduce dyskinesias and other motor symptoms that can occur with Levodopa

Question 19

How do MAO- Inhibitors work?

Answer 19

These drugs inhibit the enzyme MOA-B from breaking down dopamine which allows for dopamine to have a longer effect in the brain

Question 20

What is the purpose of Catechol-O-Methyltansferase (COMT) Inhibitors?

Answer 20

To inhibit the enzyme COMT which converts levodopa in within the periphery to an inactive metabolite. This allows for more levodopa to reach the brain to be converted into dopamine

Question 21

Which drug can be used in the early stages of PD to prolong having to take Levodopa?

Answer 21

MAO-B Inhibitors- thought to slow the progression of PD

Question 22

What is Stalevo?

Answer 22

A combination drug of levodopa, carbidopa, and COMT inhibitor

Question 23

Which Parkinsons Drugs should be used for initial treatment?

Answer 23

Dopamine Agonists or MAO-B Inhibitors

Question 24

When should patient begin taking Levodopa?

Answer 24

Should be incorporated into drug regimen as their disability increases

Question 25

What is Deep Brain Stimulation?

Answer 25

Surgically implanted electrodes into the deep brain structures where high frequency stimulation may help normalize neuronal activity within the BG- helps to resolve motor and non-motor PD symptoms