Causality assessment · Expected pharmacological effect

Entacapone and Dyskinesia: is the FAERS signal real?

n=481 co-reports · PRR 60.6 · ROR 68.4

Entacapone side-effect profile All assessments See in the full list

A written Bradford Hill assessment of one drug–event pair. The grade is a judgement about the signal, not a statement that this drug causes this event in any one person; FAERS counts are reports, not rates.

Expected pharmacological effect

Entacapone ↔ Dyskinesia

n=481 co-reports · PRR 60.6 · ROR 68.4

Entacapone is a COMT inhibitor that extends levodopa's plasma half-life; by increasing and smoothing dopamine delivery it commonly worsens or uncovers dyskinesias (481 co-reports, PRR 60.6). The effect is a direct consequence of enhanced dopaminergic stimulation, and the label advises that levodopa doses may need reduction when entacapone is added.

Regulatory basis: entacapone (Comtan) prescribing information — dyskinesia; advised levodopa dose reduction.

Bradford Hill viewpoint	Status	Note
Temporality (necessary)	met	Dyskinesia appears or worsens on starting
Strength	met	PRR 60.6, very large
Consistency	met	Reproduced across trials
Specificity	met	Specific to dopaminergic augmentation
Biological gradient	met	Related to increased levodopa exposure
Plausibility	met	Enhanced dopamine-receptor stimulation
Coherence	met	Fits the pharmacology
Experiment	met	Trials showed dose-related dyskinesia
Analogy	met	Analogous to levodopa dyskinesia

This table is this page's own qualitative read of the literature cited above, not an automated or citation-gated assessment — see the note at the bottom of this page.

✓ Trial evidence found — Effects of Carbidopa/Levodopa/Entacapone on Motor Function and Quality of Life in Patients With Parkinson's Disease (NCT00219284)

Adverse event	Immediate Switch (n=180) · Delayed Switch (n=179)
Dyskinesia	7/180	12/179

Post-marketing signal terms appear in this trial's posted adverse-event tables; per-arm counts shown as affected/at-risk. View on ClinicalTrials.gov →