Is it ok to take ibuprofen while fasting before blood work?

Depends: Most lab tests are not likely to be affected by ibuprofen. However since I do not know what tests are planned, you should run it by the doctor who is ordering the tests.

Yes but...: Make sure it doesn't bother your stomach and you don't have a history of peptic ulcer disease. Use the lowest dose possible for pain/fever and for the shortest duration possible. Some newer evidence is not showing a major lipid change between fasting and non-fasting values in relation to LDL and HDL values but fasting is still standard of care.