The anti-catalytic effect of varespladib on snake venom phospholipase A2 in vitro. (A) The varespladib concentration versus the inhibitory effect (cut-down area of varespladib group/venom alone); (B) the inhibitory effect was linearly proportional to the logarithm of varespladib concentration; and (C) the anti-catalytic activities of varespladib to D. acutus, A. halys, N. atra, and B. multicinctus. Well 1 was the positive control, filled with venom alone, well 2–5 were mixtures of venom and 0.1, 0.5, 1, and 5 μg varespladib. Abbreviations: DA: D. acutus, AH: A. halys, NA: N. atra, and BM: B. multicinctus.