Causality assessment · Causality: well established

Dapsone and DRESS syndrome (eosinophilia): is the FAERS signal real?

n=354 co-reports · PRR 27.7 · ROR 28.7

Dapsone 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.

Causality: well established

Dapsone ↔ DRESS syndrome (eosinophilia)

n=354 co-reports · PRR 27.7 · ROR 28.7

Dapsone is an antimicrobial used in leprosy, dermatitis herpetiformis, and Pneumocystis prophylaxis; the dapsone hypersensitivity syndrome — a drug reaction with eosinophilia and systemic symptoms (DRESS) of fever, rash, eosinophilia, and internal-organ involvement — appears here as 354 co-reports (PRR 27.7). It typically begins weeks after starting therapy and can be fatal, so the label advises stopping the drug and urgent assessment if it is suspected.

Regulatory basis: dapsone prescribing information — dapsone hypersensitivity syndrome/DRESS; monitoring for fever, rash, and eosinophilia.

Bradford Hill viewpoint	Status	Note
Temporality (necessary)	met	Onset weeks after starting
Strength	met	PRR 27.7, large
Consistency	met	Reproduced across case series
Specificity	met	Fairly specific to dapsone
Biological gradient	not established	Not clearly dose-related
Plausibility	met	Idiosyncratic immuno-allergic reaction
Coherence	met	Fits the DRESS picture
Experiment	n/a	Too rare for trial detection
Analogy	met	Analogous to other drug-induced DRESS

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 dapsone captured dress syndrome (eosinophilia) as a tracked adverse event in a usable structure. DRESS is rare and idiosyncratic, so treatment trials did not capture it as a coded event.