Is a platelet count of 504 10(3)/mcl high? if so, is it dangerously high?

Yes.dangerously or not depends on a many things. And u did not send norma values. Discuss with your team.

A platelet count of 504,000 is high but is usually not a serious problem. Often it is a sign of a healthy bone marrow reacting to low iron. This is very likely in a healthy 31 y/o female. Depending on blood loss during menstruation and dietary Iron intake, you are very likely to run low Iron and may even be anemic. The marrow responds by trying to increase blood cell production.

Agree with Dr. Kaplan. Your high platelet count is a likely side effect of iron deficiency from menstrual blood loss. Take oral iron and multivitamins to address a likely iron deficiency. For healthy diet: http://www.choosemyplate.gov/., exercise 30 minutes/day, drink enough water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. Wish you good health