P2X3 antagonist 34 is a potent, selective and orally active P2X3 homotrimeric receptor antagonist with IC50s of 25?nM, 92?nM and 126?nM for human P2X3, rat P2X3 and guinea pig P2X3 receptors, respectively. P2X3 antagonist 34 is less active against human, rat and guinea pig P2X2/3 heterotrimeric receptors. P2X3 antagonist 34 has strong anti-tussive effect.

NF023 hexasodium is a selective and competitive P2X1 receptor antagonist, with IC50 values of 0.21 μM, 28.9 μM, > 50 μM and > 100 μM for human P2X1, P2X3, P2X2, and P2X4-mediated responses respectively.

PPADS tetrasodiuma is a non-selective P2X receptor antagonist. PPADS tetrasodiuma blocks recombinant P2X1, -2, -3, -5 with IC50s ranging from 1 to 2.6 μM. PPADS tetrasodiuma blocks native P2Y2-like (IC50~0.9 mM) and recombinant P2Y4 (IC50~15 mM) receptors. PPADS tetrasodiuma is an inhibitor of the reverse mode of the Na/Ca²⁺exchanger in guinea pig airway smooth muscle.

AZD9056 is a selective orally active inhibitor of P2X7 which plays a significant role in inflammation and pain-causing diseases.

A-740003 is potent, selective and competitive P2X7 receptor antagonist (IC50 values are 18 and 40 nM for rat and human receptors respectively).