Drugs affecting the central nervous system ll

Question 1

What drugs are used to treat Parkinson’s disease?

Question 2

What is the pathophysiology of Parkinson’s disease?

Answer 2

Dopamine deficiency state exists in the extrapyramidal motor system, particularly in the nigrostriatal tracts.
 Levels of dopamine fall in the basal ganglia which produces a dopamine/acetylcholine imbalance with a relative increase in Ach.
 Amounts of other monoamine neurotransmitters (NA, 5-HT) somatostatin, Substance P and enkephalins are also decreased.

Question 3

Parkinson’s disease treatment is focused on correcting the DA/ACh imbalance by raising DA levels or blocking ACh.
Classes of drugs used are?

Answer 3

Drugs that raise brain DA levels or stimulate DA receptors to enhance dopaminergic mechanisms e.g. Levodopa (with Carbidopa).
Drugs with anticholinergic activity.

Question 4

Levodopa-Carbidopa adverse reactions are?

Answer 4

agitation, confusion, dyskinesias, cardiac arrythmias, hypotension, nausea, vomiting, altered libido, depression, delusions

Question 5

Contraindications of Levodopa-Carbidopa?

Answer 5

 Caution required in severe CV, pulmonary, renal, hepatic, psychiatric and endocrine diseases.
Contraindicated in wide-angle glaucoma, lactation (inhibits secretion of prolactin).

Question 6

What does COMT stand for?

Answer 6

Catechol-O-methyltransferase