Immune-mediated reaction to a medication.
Capture: List of agent + reaction + severity. Values: Agent; reaction (anaphylaxis, urticaria, angioedema, SJS/TEN, other); severity; date
Record the reaction, not just the drug. “Sulfa” without a reaction cannot be risk-stratified.
Cross-reactivity worth encoding: iodinated contrast reactions are not shellfish allergy; sulfonamide antibiotic allergy rarely cross-reacts with non-antibiotic sulfonamides.