Dopaminergic Drugs

Question 1

MOA: Increase DA release in nigrostriatal pathway

Indication: Parkinson’s Disease

SE: arrhythmia, nausea, anxiety, hallucinations,
dyskinesia and motor fluctuations (long term use)

Answer 1

L-DOPA

Question 2

AADC inhibitor

Answer 2

Carbidopa

Question 3

MOA: inhibits AADC in peripheral tissue (cannot X BBB)
Indication: concurrent rx with L-DOPA to reduce peripheral DA production
SE: augments SE of L-DOPA in CNS

Answer 3

Carbidopa

Question 4

Ergot alkaloid with D2 agonist properties

Answer 4

Bromocriptine

Question 5

Indications: Parkinson’s Disease

MOA in Parkinson’s: post synaptic activation in basal ganglia,
may also be neuroprotective (antioxidant, free radical scavenger, reduction of DA turnover)
therefore, best used early in disease course

SE: cardiac valvular fibrosis (long term use)
impulse control disorders (relatively rare)

Answer 5

Bromocriptine

Question 6

Indications: Parkinson’s Disease (lower doses), Depression (higher doses)

MOA: Selective inhibition of MAO-B (can block MAO-A at high doses),
no dietary restriction at low doses.

SE: hypotension (dizziness), dry mouth, hypertensive crisis or serotonin syndrome
at higher doses,

Contraindications: concomitant use of indirect acting sympathomimetics, or
drugs that increase serotonin neurotransmission.

Answer 6

Selegiline

Question 7

Indication: Parkinson’s Disease (more advanced)

MOA: inhibits COMT

Physiological effect: prolongs and increases effect of L-DOPA, reduces “off” time,
can reduce required L-DOPA dose

SE: dyskinesia, hallucinations, nausea, hypotension

Contraindications: liver failure (requires liver enzyme testing)

Answer 7

Tolcapone

Question 8

MOA: D2 antagonism

Indications: acute psychosis, long-term
depot for poorly compliant schizophrenic
patients

SE: extrapyramidal motor disturbances

Answer 8

Haloperidol

Question 9

DA reuptake inhibitors

Answer 9

Methylphenidate

Question 10

MOA:  Increased DA release in frontal
   cortex
Indication:  ADHD
SE: Tachycardia
Contraindication:  TCA, arrhythmia,
    hypertension

Answer 10

Methylphenidate

Question 11

Indication: Chemotherapy-induced-
and post-op nausea and vomiting, gastric paresis

MOA: D2 antagonist, also has 5-HT4 agonist properties

SE: akathisia, focal dystonia

Contraindications: long-term rx (3 months
can cause tardive dyskinesia)

Answer 11

Metaclopramide