Aspirin inhibits TXA2 and PGI2 in vivo in a dose dependent manner and daily doses as low as 20 mg have been shown to significantly inhibit TXA2 release (Warner, Nylander et al. 2011), whilst similar doses provide minimal PGI2 inhibition and no significant prolongation of the bleeding time (Kallmann, Nieuwenhuis et al. 1987). Aspirin doses of less than 75mg OD have not been studied in combination with P2Y12 inhibitors. A strategy to reduce the effect of aspirin on beneficial COX2 whilst maintaining its antiplatelet effect in the presence of ticagrelor may therefore be a lower dose than the current standard.