Matcha Drink, Stomach Issues - Starbucks, Signal Hill California

1788 East Willow Street, Signal Hill, 90755 California, United States

My sister and I ordered an iced lavender oat milk matcha earlier today. Within a few hours, we both had diarrhea, gas, and stomach aches. We thought it was our lunch that we had not long after the drinks, but our other family members didn’t feel the same. Later on the day, she feels better, but I still have slight discomfort in my stomach.
Onset: Less than 4 hours
Duration: 4 to 12 hours
Sick: 2 people
Additional information: My sister is feeling better and I am too, but I still feel some stomach pain and cramps with nausea. | Symptoms: Diarrhea, Stomach Pain, Cramps, Gas