Notice symptoms after consuming milk, ice cream, cheese, or other dairy
Look for bloating
Look for gas
Look for stomach cramps
Look for diarrhea
Look for nausea
Check whether symptoms start within 30 minutes to 2 hours after dairy
See whether symptoms improve when you avoid lactose
Try lactose-free dairy and compare symptoms
Keep a food and symptom diary
Ask a doctor about a lactose intolerance test
Ask a doctor about a hydrogen breath test
Ask a doctor about a lactose tolerance test
Ask a doctor about a stool acidity test
Get medical advice if symptoms are severe or frequent