- KEY: both transient and migratory. Appear, disappear, & pop up somewhere else.
- VERY itchy
- Can Dx by such a history alone
- Hives vanish & migrate
- Infections (viral & bacterial), esp. in children.
- Medications, esp. antibiotics & NSAIDs
- Shellfish
- Nuts
- In children: also milk, eggs, soy, wheat, tomatoes, strawberries
- Narcotics, esp. codeine (no hives; since not an IgE-mediated allergy)
- Certain parasites in returning travelers (only if there’s eosinophilia on CBC)
- Latex if excessive (e.g. gloves all day)
- Physical Urticarias, due to pressure, cold, heat, exercise, or sunlight
An association is convincing if the reaction occurred within 2 hours of food ingestion.
- Suspect a recent medication no matter when in the course it happened.