Flare

A temporary but often significant worsening of symptoms associated with a chronic illness, which can last from hours to weeks. Flares can be triggered by environmental factors (heat, pollen, weather changes), physical exertion, stress, illness, or unpredictable internal processes. During a flare, a person's baseline abilities are substantially reduced, making previously manageable tasks inaccessible. For technology design, flares underscore the importance of building systems that accommodate dramatic shifts in user capability and do not penalize reduced engagement during symptomatic periods.