What Causes Irritation In The Stomach After Taking Diclofenac?

I am 49, 5 3, weigh 123 lbs. and have been very healthy throughout my life. I am a 10-time marathoner, don t smoke, drink wine occasionally. I recently took diclofenac sodium for a foot injury (running-related). The medication caused some stomach irritation after week 2 of taking it so I discontinued use. During the time I took the medication, I had blood test performed in connection with a physical exam. I just received the results in the mail (LabCorp), which shows I have low wbc of 3.5; low neutrophils of 34; and high Lymphs of 53. Should I be alarmed, or could it be the NSAIDs causing the low levels? Thank you