Parkinsons Flashcards
Explain ‘long term levodopa syndrome’
- Premature wearing off of anti-Parkinsonian effects of Levodopa, and response fluctuations.
- Wearing off effect is time before next dose when become increasingly bradykinetic
- Response fluctuations: Dramatic swings between dyskinesias and frozen, immobile state
- ‘ON-OFF’
Levodopa induced dyskinesias and fluctuations develop earlier in ____ patients.
YOUNGER
- Management shifted towards later admin of levodopa OR
- Use of combination therapies, in effort to reduce cumulative levodopa dose
What is in…
Co-Careldopa AND Co-Beneldopa
LIST THE BRAND NAMES TOO!
Co-Careldopa:
Sinemet = Carbidopa and Levodopa
Co-Beneldopa:
Madopar = Benserazide and Levodopa
What type of enzymes are Carbidopa and Benserazide?
Peripheral dopa-decarboxylase inhibitors.
Block peripheral conversion of levodopa to dopamine and allows lower dose of levodopa to be administered
What dose is Levodopa immediate release normally started at?
10mg/day 50mg/day or 100mg/day
50mg/day
The dose then increases every 3-4 days until dose of 50mg TDS reached
What is the maximum dose of Levodopa /day that can be considered before the diagnosis of PD should be reviewed?
400mg/day 500mg/day or 600mg/day
600mg/day
List 3 common side effects seen on initiation of Levodopa therapy…
Nausea, vomiting and orthostatic hypotension (postural hypotension)
State one anti-emetic suitable for treatment of nausea and vomiting in a patient with PD
DOSE?
Domperidone 10-20mg tds
List two things that can affect absorption of Levodopa
Iron compounds and Protein in diet
What is the interaction between Levodopa and antihypertensives?
Levodopa can enhance the hypotensive effects of antihypertensive agents
What is the rough BA of Levodopa controlled release?
50-60%
60-70%
70-80%
Levodopa controlled release has a BA of 60-70% compared to Levodopa immediate release which has a BA of 90-100%
What is the response duration of immediate release Levodopa compounds?
1-3hours
What is the response duration of controlled release Levodopa compounds?
2-4hours
What is an advantage of co-prescribing controlled release Levodopa with immediate release Levodopa?
This can relieve end-of-dose deterioration/motor complications in later disease
Prevent motor complications in later PD patients but NOT drug of choice! NICE
What is the name of the intestinal gel preparation of Levodopa and Carbidopa?
Duodopa
What is an advantage of using Levodopa and Carbidopa intestinal gel? (pumped into small bowel via percutaneous route)
It is a continuous delivery which can significantly reduce motor fluctuations
Which non-ergot derived dopamine agonist is available as a patch? How long is the patch applied to the skin for?
Rotigotine - 24hr patch
List one ergot derived dopamine agonist and two non ergot derived dopamine agonists
Ergot derived = Cabergoline, Bromocriptine, Pergolide
Non ergot derived = Ropinirole, Pramipexole, Rotigotine
What annual and regular monitoring should take place when a patient is on an ergot derived dopamine agonist?
Annual chest X-Rays and ESR (Pleuropulmonary fibrosis)
AND regular echocardiographic monitoring (Cardiac valvulopathy) AND RENAL FUNC TESTS
Which of the COMT inhibitors is associated with hepatoxicity fears?
What monitoring is needed because of this?
Tolcapone - LFT’s every 2 weeks in first year
When may Tolcapone be initiated?
To reduce motor fluctuations if Entacapone fails due to lack of efficacy or side effects
At what dose is Entacapone given with each dose of Levodopa?
What is the maximum frequency of admin per day?
200mg with every Levodopa dose up to 10 doses/day
Tolcapone and Entacapone can increase dyskinesias so what can be done to combat this?
Reduce the Levodopa dose - by around 10-30%
Diarrhoea, abdominal pain, dryness of the mouth and urine discolouration is often associated with which class of drug?
COMT inhibitors
