MajorXanthine oxidase inhibitors×ACE inhibitor
Updated · Methodology
Mechanism
The combination raises risk of hypersensitivity reactions and severe skin reactions (Stevens-Johnson syndrome, toxic epidermal necrolysis, angioedema). The mechanism is not fully established; presumed to be an immune reaction to metabolites of both drugs in chronic kidney disease.
Symptoms
Rash, fever, eosinophilia, lymphadenopathy (DRESS syndrome). Severe cases: bullous rash with skin sloughing (Stevens-Johnson syndrome), angioedema of face and tongue. Symptoms appear 1–8 weeks into the combination.
Management
Avoid the combination, especially in chronic kidney disease (higher risk). Alternative to ACE-I: an ARB (losartan) for antihypertensive needs. If rash or fever emerges, stop both drugs immediately.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Summary of a multi-drug list →
Medicine list: everything you take in one place →
Sources
- FDA: Allopurinol tablet (Dr. Reddy's Laboratories Limited) – Prescribing Information (2018)– ; DailyMed setid 19a138b8-d225-03e6-f762-abe71560204b
- AEMPS: Ficha técnica: Captopril (nº registro 62305), sección 4.4 (2026)– AEMPS, CIMA, nº registro 62305, revisión 03/2026, sección 4.4