Neurological (Catechol-o-methyl transferase Inhibitor)

Question 1

Examples of drug (Catechol-o-methyl transferase Inhibitor)

Answer 1

• Entacapone

Question 2

Mechanism of action (Catechol-o-methyl transferase Inhibitor)

Answer 2

• Prevents the peripheral breakdown of levodopa by inhibiting COMT (COMT converts L-DOPA into 3-methoxy-4-hydroxy-L-phenylalanine (3-OMD). 3-OMD doesn’t cross the blood brain barrier).
• Therefore, more levodopa reaches the brain

Question 3

Indications (Catechol-o-methyl transferase Inhibitor)

Answer 3

• Parkinson’s Disease in conjunction with L-DOPA and dopamine decarboxylase inhibitor

Question 4

Side effects (Catechol-o-methyl transferase Inhibitor)

Answer 4

• Dyskinesia (common, up to 27%)
• Nausea (11%)
• Abdominal pain
• Vomiting
• Dry mouth
• Dizziness

Question 5

Important pharmacokinetics/pharmacodynamics (Catechol-o-methyl transferase Inhibitor)

Answer 5

• Rapidly absorbed

- Levodopa dose may need to be reduced by 10-30% when given with Entacapone

Question 6

Patient information (Catechol-o-methyl transferase Inhibitor)

Answer 6

• Urine may turn brown – normal
• Could become lightheaded/dizzy while doing daily activities
• Avoid abrupt withdrawal