Antifibrinolytic treatment with ε-aminocaproic acid does not restore hemostasis in f5 mutants. Offspring from f5^+/− incrosses were treated with ε-aminocaproic acid at 1 dpf and tested for venous occlusion in response to laser-mediated endothelial injury at 3 dpf, followed by genotyping. There was a slight increase in the percentage of f5^−/− embryos that formed an occlusive thrombus (14.3% vs 5.5%) compared with untreated clutchmates, but this was not statistically significant. Horizontal bars represent the median time to occlusion. ns, not significant.