Do I have to see a specialist to get a d dimer ordered?

Not necessarily.. A d-dimer test is usually obtained when a blood clot diagnosis is considered. The test is very non-specific in that many things besides a blood clot can result in a positive test. If the d-dimer is negative, the chances of having clinically significant clot is very small. So, in terms of diagnosis, a negative test is actually more helpful. The test can be ordered by any doctor.