Week 12 - Dopaminergics

Question 1

Carbidopa-levodopa (sinemet): MOA

Answer 1

• Levodopa circulates in the plasma to the BBB where it converts to dopamine
• Carbidopa inhibits the peripheral plasma breakdown of levodopa –> increases availability of levodopa at the BBB

Question 2

Carbidopa-levodopa: caution and contraindications

Answer 2

• Avoid in narrow angle glaucoma
• Avoid in patients w/ major psychiatric disorders
• Avoid in patients w/ malignant melanoma
• Caution w/ patients who have CVD
• Risk of neuroleptic malignant syndrome if abruptly stopeed

Question 3

Carbidopa-levodopa: ADR

Answer 3

Orthostatic hypotension, somnolence, dizziness, HA, depression, nausea, constipation, dyskinesia, HTN, insomnia, abnormal dreams (hallucinations)

Rare: neuroleptic malignant syndrome, peripheral neuropathy

Question 4

In what conditions are dopaminergics used?

Answer 4

Parkinsons

Attempt to restore the functional balance of dopamine and acetylcholine in the corpus striatum of the brain

Question 5

How long may it take patients to achieve maximum therapeutic effects?

Answer 5

6 months

Question 6

Dopaminergics: patient education

Answer 6

Avoid abrupt discontinuation

Question 7

Dopaminergics: drug interactions

Answer 7

Drugs that decrease effectiveness of dopaminergics - TCAs

Dopaminergics may increase the effectiveness of HTN drugs

Avoid antacids