It is always wise to convert medicalese to English while teaching the public. I had to look it up to be sure my guess was right.... Post = after 2 hours would indicated an event. I was wondering if it was 2 hours after rising, but there were better word choices for that. I didn't think it could possibly be after a meal because I always had to be tested fasting, even with regard to coffee with creamer. It turned out to be 2 hours after a meal. So, for anyone confused but not willing to look it up... 2 HOURS AFTER LUNCH OR DINNER. I would assume with no other snacking.
during or relating to the period after dinner or lunch.
"we were jolted from our postprandial torpor"
occurring after a meal.
"an annual postprandial blood glucose test"