PGD2 functions as a neuromodulator as well as a trophic factor in the central nervous system.

PGD2 is also involved in smooth muscle contraction/relaxation and is a potent inhibitor of platelet aggregation.

[6] Furthermore, PTGDS and its product PGD2 are elevated in the bald-scalp areas of men with male pattern baldness (androgenetic alopecia).

[7] Prostaglandin D2 synthase is used clinically as a diagnostic marker for liquorrhea, that is, to check whether fluid leaking from the nose or ear contains cerebrospinal fluid.

In a medical context, the older term "beta-trace protein" is frequently used to refer to PTGDS.