A 25-year-old reports bloating and watery diarrhea 30–60 minutes after drinking a glass of regular milk but no hives, respiratory symptoms, or systemic reactions. Which management plan is most appropriate to recommend initially?

• A. Advise strict lifelong avoidance of all dairy proteins and prescribe epinephrine auto-injector since these GI symptoms indicate IgE-mediated milk allergy, which misinterprets intolerance symptoms as anaphylaxis risk without allergic features.
• B. Recommend a high-lactose diet to desensitize the gut microbiome immediately without any graded approach or supplements, a strategy that may worsen symptoms and lacks evidence as first-line management.
• C. Suggest immediate colonoscopy and biopsy to look for lactase-producing tumors in the colon before any dietary changes, an invasive and inappropriate first step for typical lactose intolerance symptoms.
• D. Recommend trial of lactose-free dairy alternatives or over-the-counter lactase enzyme supplement taken with milk and monitor symptom improvement to distinguish lactose intolerance from other causes.

Answer: (D)