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Causality: well established
Causality assessment · Causality: well established
Pimozide and Prolonged QT interval: is the FAERS signal real?
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.
Pimozide ↔ Prolonged QT interval
n=23 co-reports · PRR 28.5 · ROR 29.9
Pimozide prolongs the QT interval and carries a boxed warning for this proarrhythmia, with ECG assessment advised before and during therapy; 23 co-reports give PRR 28.5. The label limits dose and warns against QT-prolonging co-medication.
Regulatory basis: pimozide (Orap) prescribing information — boxed warning for QT prolongation/torsades; ECG monitoring.
| Bradford Hill viewpoint | Status | Note |
|---|---|---|
| Temporality (necessary) | met | Hours after dosing |
| Strength | met | PRR 28.5, an extreme signal |
| Consistency | met | Reproduced across reports |
| Specificity | met | Fairly specific to pimozide |
| Biological gradient | met | Dose-related |
| Plausibility | met | Known hERG blockade |
| Coherence | met | Fits pimozide's cardiac effect |
| Experiment | n/a | Small numbers limit trial capture |
| Analogy | met | Analogous to other antipsychotic QT effects |
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.
✗ No ClinicalTrials.gov results-posting trial in the top search hits for pimozide captured prolonged qt interval as a tracked adverse event in a usable structure. QT effect is expected but the small treated population limits statistical capture.